NCERT Solutions Class 6 Science Chapter 11 Nature's Treasures

F R E E S T U D Y M AT E R I A L F O R E V E R Y S T U D E N T

CLASS 6 · SCIENCE

NCERT Solutions

Chapter 11: Nature’s Treasures

NCERT Textbook — Curiosity

BOOK PAGES SECTIONS QUESTIONS MEDIUM

207 – 230 24 56 English

Solutions, notes, sample papers & more at 61 pages

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

CLASS 6 · SCIENCE · CURIOSITY

NCERT Solutions — Chapter 11: Nature’s Treasures
Complete NCERT Solutions for Class 6 Science Chapter 11 Nature’s Treasures from the NCERT textbook
Curiosity. Every question of the chapter is answered — Activities 11.1 to 11.6 with their tables filled in, all the
in-text questions from pages 207 to 225, and the full Let us enhance our learning (pages 227–229) and
Learning further (pages 229–230) exercises, with real Indian examples of coalfields, wind farms, forests and
traditional water harvesting.

TEXTBOOK BOOK PAGES

Curiosity (Class 6) 207 – 230

SECTIONS QUESTIONS

24 56

MEDIUM

English

In-text Questions — Page 207
Chapter opening — Ajji’s village in the Western Ghats

Q1 Can you think of more such treasures of nature?

Ajji has already named four treasures — pure air, fertile soil, plenty of sunlight and trees that
feed and shelter animals. Many more can be added, and each one is something we did not
make.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

TREASURE OF WHY IT IS A TREASURE
NATURE

Water Streams, rivers, ponds, rain and groundwater — for drinking, cooking, bathing and
growing crops

Forests Wood, fruits, honey, gum, medicines, and a home for birds, insects and wild animals

Soil Holds the roots, stores water and nutrients, and grows all our food

Wind Winnows grain, sails boats, turns windmills and generates electricity

Rocks and minerals Stone for houses and roads; iron, copper, aluminium and gold from minerals

Plants and animals Food, milk, cotton, wool, honey, wood and medicines

Fossil fuels Coal, petroleum and natural gas buried deep inside the Earth

Why the book calls them treasures: a treasure is something valuable that we did
not earn but must guard. Nobody manufactured air, soil or a river — nature gave
them to us free. And unlike money, if they are spoilt or finished, no shop can sell us
more.

Try This: Stand outside your home for five minutes and list ten things you can see or
feel that nobody made — sunlight, breeze, birdsong, a neem tree, clouds, soil, ants…
That list is your own “treasures of nature”.

Activity 11.1: Let us experience — Page 208
11.1 Air — Holding your breath

ACTIVITY

Q1 Take a deep breath in, and then breathe out slowly. Take a deeper breath in again.
Hold your breath for as long as you can and then breathe out slowly. How long can
you hold your breath?

Most Class 6 students can hold their breath for about 25 to 45 seconds. A trained swimmer
may manage a minute or more, and after running about, the time drops to only 10–15 seconds.
How to do it properly:

Sit still and calm. Ask a friend to time you with a watch or by counting slowly.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Breathe in deeply, hold, and stop the moment you feel uncomfortable — then breathe out
slowly.
Repeat two more times and write down all three timings.

TRY TIME HELD (SAMPLE READINGS)

First try 28 seconds

Second try 35 seconds

Third try (after running) 14 seconds

Why the time is short: the air we breathe in contains oxygen. Our body needs a
steady supply of oxygen to do its work. When we hold our breath, no fresh oxygen
reaches the body, so within seconds it forces us to breathe again.

Caution (from the book): Do not hold your breath for so long that you start feeling
uncomfortable. Never try this in water.

Q2 How do you feel when you hold your breath?

At first nothing happens, but very soon there is a strong, uncomfortable urge to breathe.

A heaviness or tightness in the chest.
The heart beats faster.
A burning feeling in the throat and a wish to gasp.
If held longer — giddiness and the face turning red.
Great relief the moment you breathe out and take fresh air in.

Why it happens: the body cannot store oxygen. When we hold our breath the body
does not get enough oxygen to carry on its functions, and the used-up carbon
dioxide keeps collecting in the blood. The body senses this and forces us to breathe.
That is why we can live for days without food or water, but not for even a few
minutes without oxygen.

In-text Questions — Page 209

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Class 6 Science Chapter 11 Nature’s Treasures
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11.1 Air — Fig. 11.1 Composition of air
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Oxygen — about 21%; this is the gas we need to stay alive.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Did you know? Percentage means “the number of parts in 100”, written with the
symbol %. So 21% oxygen means 21 parts of every 100 parts of air are oxygen.

Activity 11.2: Let us make and decorate — Page 210
11.1 Air — Making a firki (paper pinwheel)

ACTIVITY

Q1 Now, you can hold the firki in your hand and run. You can also blow air on it. What
do you observe? Does the firki rotate?

Yes — the firki rotates every time air pushes against its blades.

WHAT YOU DO WHAT YOU OBSERVE

Hold the firki still in still air It does not turn

Blow air on it It turns; blow harder and it turns faster

Hold it up and run It spins fast on its own

Move it back and forth It rotates each time it is moved

Stand still on a windy day It keeps rotating without you doing anything

Why it turns: the blades of a firki are folded, so each blade is slanted. Air striking a
slanted blade gives it a sideways push. All four blades are pushed the same way
round, so the whole firki spins on its pin. When you run, you move through still air —
which is the same as air moving past you.

Tip: Use a square of stiff, thin paper 15 cm × 15 cm and do not push the all-pin too
tight into the stick. If the pin is tight, the firki will not spin however hard you blow.

Q2 What makes a firki rotate?

It is the wind — moving air — that makes a firki rotate.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

We cannot see air, but we can see what it does. Air makes the leaves of a tree rustle, clothes on
a line sway, and the pages of an open book flutter under a fan. In the same way, moving air
pushes the slanted blades of the firki and turns it.

Moving air = wind

Gentle wind = breeze • Very fast wind = storm

The big idea: a windmill works exactly like a firki, only much bigger — the wind
rotates its wings. Windmills are used to run flour mills, to pull water up from a well
and to generate electricity. In a windmill farm, a large number of windmills stand
together and generate electricity from the wind.

More to know! — Page 210
11.1 Air — Windmill farms of India

MORE TO KNOW!

Q1 Muppandal Wind Farm in Tamil Nadu, Jaisalmer Wind Park in Rajasthan and
Brahmanvel Wind Farm in Maharashtra are some of the leading windmill farms in
our country. Find out more other windmill farms in our country.

India is one of the largest wind-power producing countries in the world. Wind farms are built
where the wind blows strong and steady — along the coasts, in the passes of the Western Ghats
and in the open desert.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

WIND FARM STATE WHY THE WIND IS STRONG THERE

Muppandal (near Tamil Nadu Sea winds rush through the Aralvaimozhi gap in the
Kanyakumari) Western Ghats — one of Asia’s largest wind farms

Kayathar and Tamil Nadu Same windy corridor near Tirunelveli–Thoothukudi
Aralvaimozhi

Jaisalmer Wind Park Rajasthan Open, flat Thar Desert with nothing to block the wind

Brahmanvel and Maharashtra High ridges of the Satpura and Sahyadri hills
Dhule–Sakri

Vankusawade (near Maharashtra Windy crest of the Western Ghats
Koyna)

Chitradurga and Karnataka Open plateau of north Karnataka
Gadag

Kutch and Jamnagar Gujarat Strong sea breeze all along the Saurashtra–Kutch coast
coast

Anantapur and Andhra Dry, open Rayalaseema plateau
Ramagiri Pradesh

Why wind energy is worth it: wind is a renewable resource. Once the windmill is
built it needs no coal, no diesel and it gives out no smoke. The five states above —
Tamil Nadu, Gujarat, Karnataka, Maharashtra and Rajasthan — together produce
most of India’s wind electricity.

Find out: Ask at home or search in an atlas whether your own state has a wind farm.
If it does not, think why — is your area shielded by hills, or too far from the coast?

In-text Questions — Page 211
11.2 Water — Uses and sources of water

Q1 How do you feel when you cannot get water to drink, especially when you are
thirsty?

Very uneasy and restless — and the feeling grows quickly.

The mouth and throat go dry, and it becomes hard even to speak.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

You feel weak, tired and irritable, and cannot pay attention to anything else.
After a long time without water — headache and giddiness.
You can think of nothing but water until you get a glass of it.

Why we feel this way: more than half of our body is water. We keep losing it
through sweat, breath and urine, so it has to be replaced. Thirst is the body’s own
alarm telling us the water is running low. That alarm is why water is called precious
— a person can survive for days without food, but only a few days without water.

Think about it: In summer, many Indian towns keep a pyaau or a matka of drinking
water outside shops and temples for passers-by and birds. That old custom exists
exactly because everyone knows this feeling.

Q2 Can you think of some more uses of water in your daily life? Write down your
responses in the blank bubble.

The first bubble already says “We need water for drinking.” Here is what can go in the blank
bubbles.

WHERE WATER IS EXAMPLES
USED

At home Cooking, washing utensils, washing clothes, bathing, cleaning the floor, flushing the
toilet, watering plants

On the farm Irrigating fields, preparing the soil, giving water to cattle

In industry Making paper, cloth, cement, sugar and steel; cooling machines

For everyone Generating electricity in dams, putting out fires, transport by boat, fish farming

Notice the pattern: almost every use except drinking can be done with less water,
or with water that has already been used once. That is where saving becomes
possible.

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Class 6 Science Chapter 11 Nature’s Treasures
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Where do we get water from? Make a list of the different sources of water.
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Water

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KIND OF WATER SOURCES CAN WE USE IT?

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Saline (salty) water No — not fit for domestic, agricultural
or industrial use

Frozen freshwater Ice sheets, snow on high mountains and
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Underground Groundwater drawn by wells, tube wells
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Freshwater, but not easy to reach

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freshwater and hand pumps

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a why Ajji teaches the children to use every drop with care.
shortage. That is exactly

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.2 Water — Is water being wasted?

Q1 Do you feel that water is being used efficiently in our daily activities? Have you
observed water being wasted in your daily activities?

No — in most homes and schools water is not used efficiently. Once you start looking,
wastage is visible everywhere.

The tap left running while brushing teeth, soaping hands or shaving.
Leaking taps and pipes — a tap dripping once a second wastes several buckets a day.
Overflowing overhead tanks because nobody switched the motor off.
Washing a scooter, a car or the courtyard with a running hosepipe.
Watering the garden at noon, when much of it simply evaporates.
Running the washing machine or the tap for just two or three utensils.

Why we do not notice: water arrives at the turn of a tap, so it feels endless. But
behind that tap is a river, a lake or a borewell that is not endless at all. In many parts
of India people have to walk long distances to fetch drinking water — and everyone
does not have the same access to it.

Check it yourself: Put a mug under a dripping tap in the morning and see how
much has collected by evening. That is the water one small leak throws away every
single day.

Activity 11.3: Let us find out — Page 212

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.2 Water — Table 11.1 Wastage of water in your daily activities

ACTIVITY

Q1 Fill the Column II and Column III in Table 11.1: Wastage of water in your daily
activities — 1. Hand washing 2. Washing clothes 3. Washing utensils 4. Taking
shower 5. Cooking 6. Gardening 7. Brushing teeth

TABLE 11.1: WASTAGE OF WATER IN YOUR DAILY ACTIVITIES

COLUMN I COLUMN II COLUMN III

ACTIVITY HOW IS WATER SUGGEST WAYS TO REDUCE WASTAGE OF
WASTED? WATER.

1. Hand washing

2. Washing
clothes

3. Washing
utensils

4. Taking shower

5. Cooking

6. Gardening

7. Brushing teeth

Table 11.1 as printed on page 212 — Column II and Column III are blank for you to fill.

Here is Table 11.1 completed. Fill your own copy after watching what actually happens at your
home.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

ACTIVITY HOW IS WATER WASTED? WAYS TO REDUCE WASTAGE OF WATER

1. Hand The tap runs while soaping the hands Close the tap while soaping; open it only to rinse;
washing use a half-open tap

2. Washing Machine run half-empty; too many rinses; Run a full load; soak clothes first so less
clothes soapy water thrown away scrubbing is needed; use the rinse water to wash
the floor or the courtyard

3. Washing Tap kept running throughout; utensils Scrape the leftovers first, soap all the utensils
utensils washed one by one together, then rinse in a tub of water

4. Taking A long shower uses far more water than Bathe with a bucket and mug; keep the shower
shower needed; water runs while soaping short; fix a low-flow shower head

5. Cooking Vegetables washed under a running tap; Wash vegetables in a bowl; use the leftover water
extra water in which rice or dal was boiled for plants or for kneading dough; take only as
is thrown away much water as needed

6. Gardening Hosepipe left on; watering in the hot Water early morning or evening with a can; put
afternoon so most of it evaporates dry leaves (mulch) around the plants; use drip
watering

7. Brushing The tap keeps running for the full two Use one glass of water; close the tap while
teeth minutes brushing

Tip: Ajji’s method in the story is the simplest rule of all — water the plants in such a
way that every drop is used and none goes waste.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q2 What conclusion can you draw from the information you gathered in the table?
What can you and your family do to reduce this wastage of water?

TABLE 11.1: WASTAGE OF WATER IN YOUR DAILY ACTIVITIES

COLUMN I COLUMN II COLUMN III

ACTIVITY HOW IS WATER SUGGEST WAYS TO REDUCE WASTAGE OF
WASTED? WATER.

1. Hand washing

2. Washing
clothes

3. Washing
utensils

4. Taking shower

5. Cooking

6. Gardening

7. Brushing teeth

Table 11.1 as printed on page 212 — Column II and Column III are blank for you to fill.

Conclusion: most of the water we waste is not wasted by any one big activity — it leaks away in
small amounts, many times a day, in ordinary jobs like brushing, bathing and rinsing. Almost
all of it can be saved by small changes of habit that cost nothing.
What a family can do:

Turn off taps when they are not in use, and fix every leakage at once.
Bathe with a bucket and mug instead of a shower.
Recycle water — use the water from washing vegetables and rinsing clothes for plants,
floors and the courtyard.
Do water harvesting — collect rainwater from the roof in a tank or lead it into a pit so it
soaks into the ground.
Fit a float valve on the overhead tank so it never overflows.
Make one person the “water monitor” each week to check taps and report leaks.

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Class 6 Science Chapter 11 Nature’s Treasures
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Why it adds up: if one family saves even 50 litres a day, a colony of 100 families

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saves 5,000 litres a day — a full tanker. Saving water also saves the electricity used to
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In-text Questions — Page 213
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11.2 Water — Pollution, conservation and waterem
harvesting

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Identify other human activities that lead to water pollution. Discuss with your
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friends in the class what you can do to reduce water pollution.

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e mentions two: throwing trash into water bodies and dumping waste from homes
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The

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HUMAN ACTIVITY HOW IT POLLUTES WATER

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Letting untreated sewage and drain water flow into Adds filth and germs; the water starts to smell and
rivers fish die

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Factory waste — dyes, acids, oil, chemicals Adds harmful substances that do not go away by
themselves
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Excess and pesticides in fields Rain washes

agl Washing clothes, cattle and vehicles in ponds and Soap, detergent and grease mix into the water
rivers
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Throwing plastic bags, wrappers, idols and Plastic floats for years and blocks the flow

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offerings into rivers

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Open defecation near a water source Germs enter the water and cause diseases

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Oil leaks from boats and ships
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and fish

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What we can do (discuss and choose in class):

Never throw wrappers, bottles or leftover food into a pond, canal or river — carry them to a
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dustbin.

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Use less detergent, and wash clothes at home rather than at the river bank.
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Immerse idols and puja flowers in a separate tank, not in the river.
Keep the school and a g drains clean and unblocked.
colony
Make posters and a street play for cleanliness week; join a river or lake clean-up drive.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Why it matters so much: polluted water is not fit for consumption by any living
being — not for us, not for cattle, not for the fish that live in it. And freshwater
sources are already limited.

Q2 In what ways can you conserve water?

Conserving water means using it carefully and putting back whatever we can. Three
groups of methods:

METHOD WHAT TO DO

Use less Close taps when not needed; bathe with a bucket; fix leaks; wash vegetables in a bowl; run
a full washing machine load

Use again (recycling) Use rinse water and RO reject water for plants, floors and toilets; use vegetable-washing
water in the garden

Put water back Rooftop rainwater harvesting; recharge pits and soak pits; check dams, ponds and
(harvesting) stepwells; keep some ground unpaved so rain can seep in

Waste less in farming Drip and sprinkler irrigation instead of flooding the field; mulching with dry leaves

Keep it clean Preventing pollution is also conservation — clean water stays usable

Why it is urgent: freshwater sources are limited, so there is a shortage of water in
many parts of India. At some places people walk long distances just to fetch
drinking water. Everyone does not have the same access to water — so using it
judiciously is not only sensible, it is fair.

Q3 Find traditional water harvesting practices in your locality. Discuss with your
teachers and parents to learn more about it.

Almost every region of India worked out its own way of catching and storing rain long before
pipes and pumps existed. Find out which of these belongs to your area.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

TRADITIONAL REGION HOW IT WORKS
SYSTEM

Bawadi / Baoli Rajasthan Deep stepped well; stores rainwater and water
(stepwell) seeping in from nearby lakes and ponds — e.g. Toorji
ka Jhalra, Jodhpur

Vav Gujarat Stepwell, such as Rani ki Vav in Patan and Adalaj ni Vav

Johad, Tanka, Rajasthan Earthen check dam; underground tank under a
Khadin, Kund courtyard; embankment that holds runoff on farmland

Ahar–Pyne Bihar (Magadh) Channels (pyne) lead river and rain water into a
reservoir (ahar)

Eri / Kere (tanks), Tamil Nadu, Karnataka Chains of village tanks and temple tanks that fill one
Kalyani after another

Phad and Bandhara Maharashtra Diversion channels from a stream to the fields

Kuhl / Kul, Naula, Himachal Pradesh, Small canals from a glacier stream; stone-lined spring
Guhl Jammu, Uttarakhand tanks

Bamboo drip Meghalaya, Nagaland Split bamboo pipes carry spring water; rain caught on
irrigation, Zabo hill terraces

Surangam, Zing, Kerala, Ladakh, Tunnel well in laterite; tank for glacier melt; shallow
Virda Kutch (Gujarat) well in a sandy hollow

How to do this task: ask your grandparents or an elderly neighbour whether the village had a
talab, johad, baoli, kere or temple tank; find out who looked after it, and whether it still holds
water. Then draw a simple sketch of it and write five lines about it.

Did you know? A stepwell stores not only rainwater but also water that seeps in
from nearby lakes, ponds and rivers. Its trench walls are lined with blocks of stone
laid so that water can pass between them.

In-text Questions — Page 214

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.3 Energy from the Sun — World Water Day and uses of sunlight

Q1 World Water Day is observed on 22nd March every year. Find out its importance.

World Water Day is observed on 22 March every year to remind the whole world that
freshwater is limited and must be valued, shared fairly and kept clean.

It was started by the United Nations and has been observed since 1993.
Every year has a theme — for example groundwater, glaciers, or water for peace — so that
one problem gets everybody’s attention.
Its main goal is that every person on Earth should get safe drinking water and
sanitation.
Schools, panchayats and towns mark it with rallies, cleaning of ponds and wells, poster and
slogan competitions, and pledges to fix leaking taps.

Why a whole day for water: a very small fraction of the Earth’s water is freshwater
that is easy to reach, and it is shared by every human being, animal and plant. A
fixed day each year makes governments report what they have done and makes
ordinary people think about their own habits.

Try This: On 22 March, count the taps in your school, check how many drip, and
hand the list to your teacher. That is a real World Water Day activity, not just a poster.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q2 We use heat and light from the Sun for various purposes. What are some of the
activities for which we need heat and light? Bhoomi draws some pictures to show
the uses of heat and light from the Sun. Help her by adding more examples. Draw
the pictures and write their descriptions in the space provided.

Plants make food Drying of clothes

The picture spaces printed on page 214 — Bhoomi's two pictures, and three empty boxes
to fill in.

Bhoomi has already drawn two — plants making food and drying of clothes. Here are more
pictures you can add, with their descriptions.

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Class 6 Science Chapter 11 Nature’s Treasures
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PICTURE TO DRAW DESCRIPTION TO WRITE UNDER IT

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Chillies / mango slices on a
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The Sun’s heat dries them so they can be stored and used when fresh ones are

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mat not available — exactly what Ajji is doing

gl and vadis drying on
aPapads Sun-drying removes water so the food does not spoil
the terrace

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Grain spread out on the
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Farmers dry paddy and wheat in the Sun before storing it ag
threshing floor
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Solar panels on a roof
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They capture the Sun’s energy and produce electricity

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Solar cooker
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Food is cooked directly by the Sun’s heat, with no fuel

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Solar water heater Water for bathing is heated by the Sun
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a g Salt pans by the sea Sea water evaporates in the Sun and leaves common salt behind — as in
Gujarat and Tamil Nadu

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Clothes and books put out in Sunlight dries the damp and keeps away fungus and germs

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winter sunshine

A child playing outdoors in the g l
a Sunlight helps our body make vitamin D for strong bones
morning Sun

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The water cycle — sea, cloud, The Sun’s heat evaporates water and gives us rain

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rain

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otherwise need fuel, electricity or money. That is why the Sun is called the main
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In-text Questions — Page 215
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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.3 — The cow, the grass and the Sun

THINK AND ANSWER

Q1 (Conversation about the grazing cow) According to you, whose statement is correct
and why?

The last child is correct — the one who says: “The cow is eating grass. Grass leaves need
sunlight to grow. So, the main source of energy is the Sun. This way the cow gets energy from
the Sun.”
Let us look at each statement:

STATEMENT CORRECT? REASON

“The cow is grazing the grass and Partly right True as far as it goes — the cow does get its energy
getting energy from it.” from the grass. But it stops at the grass and does not ask
where the grass got the energy from.

“The cow is standing in the Sun, Right about Correct that an animal cannot take in energy simply by
but that does not mean it is one thing standing in sunlight — animals cannot make food from
getting energy from the Sun.” sunlight. But wrong to conclude that the Sun gives the
cow no energy.

“The cow eats grass; grass needs Fully correct It follows the energy all the way back to where it
sunlight to grow; so the main started.
source of energy is the Sun.”

Sun → sunlight helps grass prepare food → cow eats the grass → cow gets energy

So the Sun is the main source of energy for the cow, though not directly.

Why the second child is mistaken: a cow standing in the Sun only gets warm — it
cannot turn sunlight into food. Only green plants can do that. So sunlight reaches
the cow through the grass, not through its skin. The same is true for us: our
chapati, dal, milk and egg are all sunlight stored by plants.

In-text Questions — Page 216

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.3 — What if the Sun were not visible?

THINK AND ANSWER

Q1 What will happen if the Sun is not visible for a few days? 1. We may have to depend
on artificial lighting during day time also. 2. ......... 3. .........

Point 1 is already filled in by the book. Here is what can go in points 2 and 3 — and several
more.

1. We may have to depend on artificial lighting during day time also. (given)
2. Clothes, grain, papads and chillies will not dry, and damp clothes will smell and grow
fungus.
3. Solar panels, solar cookers and solar water heaters will stop working, so there will be
less electricity and no free hot water.
4. It will become cold — the Sun is what warms the land, the air and the water.
5. Plants will not be able to make food properly, so leaves turn pale and crops grow poorly.
6. Animals that feed on plants will go short of food, and so, in the end, will we.
7. Less evaporation from seas and rivers means fewer clouds and less rain later.
8. Many flowers will not open, birds will be confused about when to feed, and people will feel
dull and sleepy.

Why so much depends on one star: the Sun gives every living being on Earth both
heat and light. Plants get energy from the Sun and produce food; animals eat
plants; we get food from both. This whole cycle on Earth is possible only because of
the Sun. That is why one cannot imagine life on Earth without it.

In-text Questions — Page 217
11.4 Forests — What we get from forests

Q1 Discuss with your friends and make a list of at least five products that we get from
forests.

Far more than five — here is a full list you can pick from.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

PRODUCT WHAT IT IS USED FOR

Wood / timber (sal, teak, deodar) Furniture, doors, windows, boats, farm tools

Firewood and charcoal Cooking and heating

Bamboo and cane Baskets, mats, ladders, huts, scaffolding, agarbatti sticks

Fruits, nuts and seeds Amla (nellikai), jamun, mahua, tamarind, chironji

Medicinal plants Neem, tulsi, ashwagandha, sarpagandha, giloy

Honey and beeswax Food and candles — collected in the Sundarbans and Nilgiris

Gum, resin and lac Gum from babool, resin from chir pine, lac for bangles and polish

Tendu leaves and sal seeds A source of income for many forest-dwelling families

Paper and plywood raw material Pulpwood from plantations

Fodder and green leaf manure Feed for cattle and goats; leaves ploughed back into fields

The products we cannot pack in a bag: a forest also gives clean air, shade and
cool weather, rain, and it holds the soil with its roots so that it is not washed away.
It is a natural home for wild animals, birds and insects. These free services are worth
more than everything in the table above.

Note Ajji’s rule: in her village they do not pluck fruits from the trees — only the
fallen ones are collected, so that the fruit is left for animals and birds. That single
custom keeps the forest feeding everyone.

Q2 What are the consequences of cutting a large forest area? Make a presentation or
do a role play, or write a story or a poem that shows what could happen if we
continue to cut down trees in our forests.

What must go into your presentation, play, story or poem: the effects come one after
another, like falling dominoes.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

WHAT HAPPENS FIRST WHAT FOLLOWS

Roots no longer hold the soil Rain washes the fertile topsoil away; the land becomes barren; rivers and
dams fill with silt

No leaf-fall on the ground No decaying leaves, so the soil loses its nutrients

Fewer trees to soak up rain Water runs off quickly — floods in the rains, dry wells in summer

Homes of animals destroyed Birds, insects and wild animals lose food and shelter; elephants and leopards
stray into villages

Less shade, fewer trees The area becomes hotter and drier

Fewer trees to absorb carbon More carbon dioxide stays in the air; the air becomes more polluted
dioxide

Forest produce disappears Families who live on honey, tendu leaves and medicinal plants lose their
livelihood

It takes many years to grow a new The loss is not repaired in our lifetime
forest

Sample story outline (adapt it in your own words):

“The Last Tree of Devgarh” — Devgarh village sits below a green hill. Every year a few
more trees are cut for timber. The children still find amla and mahua. Ten years later
the hill is bare. The monsoon comes and, with no roots to hold it, the soil slides
down and buries the fields. In summer the well runs dry and the peacocks stop
coming. Old Ajji tells the children about the Chipko movement — how in the early
1970s in Uttarakhand, local women encircled and hugged the trees to protect them
from being felled. The children begin a Van Mahotsav in Devgarh, plant saplings on
the hill, and promise each sapling a name and a caretaker. Years later, the peacocks
return.

Why a story works better than a lecture: the loss of a forest is slow, so nobody
notices it year by year. A story compresses twenty years into five minutes and lets
the audience see the change.

Activity 11.4: Let us investigate — Pages 218 & 219

Page 23 of 61

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Class 6 Science Chapter 11 Nature’s Treasures
a g l AglaSem · NCERT Solutions

11.5 Soil, Rocks and Minerals — Table 11.2 Soil samples
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ACTIVITY

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a s em samples of soils from different areas around your home and school. Guess
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what could be there in different soils. Observe carefully each soil sample and note
its colour. Touch each soil sample and feel its texture. Observe the soil samples with

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gl filled in with typical observations.
Collect

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

LOCATION FROM WHAT I OBSERVATION WITH OBSERVATION WITH
WHICH SOIL GUESSED NAKED EYE (COLOUR MAGNIFYING LENS
SAMPLE WAS ABOUT THE AND TEXTURE)
COLLECTED SOIL

Soil from a farm after Soft, dark and Dark brown, loose and Fine grains of different
ploughing moist crumbly; slightly damp; smells sizes, bits of dry root and
earthy leaf, a few tiny insects

Soil from the school Hard and dusty Light brown, hard, packed Mostly sand grains and
playground tight, very little moisture small pebbles; almost no
plant matter

Soil from under a big Full of leaves Very dark, soft and spongy; Half-rotted leaves, root
tree cool and damp hairs, ants, a small
earthworm

Soil from a river or Sticky Greyish, smooth, sticky when Very fine particles, few big
pond bank wet; can be rolled into a thread grains, tiny shells

Sand from a heap or a Loose and rough Pale yellow-grey, rough and Separate shiny grains, all
dry stream bed gritty, runs through the roughly the same size
fingers

Caution (from the book): Wash your hands thoroughly after touching soil collected
from different places. Soil that has garbage in it sometimes carries germs that may
be harmful.

Q2 Is there any difference between your guess and what you can actually observe
when you look closely?

Yes — and that is the whole point of the activity. A guess is made from memory; an
observation is made from looking.

WHAT WE USUALLY GUESS WHAT WE ACTUALLY FIND

“Soil is just mud” It contains sand, clay, pebbles, roots, dead leaves, insects and worms

“All soil is brown” Samples are dark brown, red, grey, black or pale yellow

“Soil has nothing alive in it” Ants, worms and many organisms too small to see are living in it

“All soils feel the same” One is gritty, another silky, another sticky

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Why guessing first is still useful: in science we always make a guess before we test
— the guess tells us what to look for, and the surprise tells us we have learnt
something new.

Q3 Do you see any differences in the soil samples taken from different places?

Yes — every sample is different in colour, texture and in what it contains.

Colour — farm soil dark brown, forest soil almost black, a river bank grey, and soil in parts of
Maharashtra, Chhattisgarh and Tamil Nadu deep red.
Texture — sandy soil is gritty and loose, clayey soil is smooth and sticky, loamy soil is
crumbly.
Moisture — forest soil under fallen leaves stays damp; playground soil is dry.
Living things — plenty of worms and insects in garden and forest soil, hardly any in road-
side or playground soil.

Why they differ: the soil samples collected from different places may be of different
colours because they contain different materials. Soil is formed from the rock
lying beneath it, so a different rock gives a different soil. Plants and animals also
become part of the soil as they decompose and decay, so places with more plant life
have darker, richer soil.

Did you know? There are different types of soil — some are good for growing
certain types of plants, while some are good for making bricks for buildings. Forests
have a variety of soils, which is why soil is called a precious treasure that supports
biodiversity.

Q4 Do you see differences in what you are able to observe with your naked eye and
what you can observe with a magnifying lens?

Yes — the magnifying lens shows far more than the naked eye.

Page 26 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

WITH THE NAKED EYE WITH A MAGNIFYING LENS

Soil looks like one brown powder Separate grains of many sizes and colours become visible

Only big pebbles and leaves are seen Tiny bits of dry root, broken leaf and seed coat are seen

No living thing appears Mites, ants’ eggs and other very small creatures appear

Texture has to be judged by touch You can actually see whether the grains are round, sharp or flat

Why the lens matters: there may be many small organisms in the soil that we
cannot see with our naked eyes at all. A magnifying lens is a scientist’s way of
looking harder — the soil has not changed, only our ability to observe it.

In-text Questions — Page 219
11.5 — How soil is formed

Q1 Have you ever wondered how soil is formed?

Soil is formed by the disintegration (breaking apart) of rocks by the action of the Sun,
water and living organisms over a long time — thousands of years.

Rock Heat of the Sun, rain and flowing
water, wind, and the roots of plants
break the rock apart, bit by bit

Small pieces of rock —
sand, silt and clay
Fallen leaves, dead plants and
animals decay and mix in, adding
nutrients to the broken rock
SOIL
air • water • living things The whole process takes thousands of years

How soil is made: rock is broken apart by the Sun, water and living things, and the pieces mix with
decayed plant and animal matter.

The agents that break the rock:

Page 27 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

The Sun — rock heats up by day and cools at night, expanding and contracting until it
cracks.
Water — rain seeps into cracks; flowing river water rubs pieces of rock against one another
and rounds them into pebbles and sand.
Living organisms — roots push into cracks and widen them; lichens and moss slowly eat
into the rock surface; worms and insects mix everything up.

Why soil is called non-renewable: a few centimetres of soil take hundreds to
thousands of years to form, but one heavy shower can wash that away from a bare
hillside in a single afternoon. That is why forests, which hold soil with their roots,
matter so much.

Recycling in nature (from the story): the leaves that fall from trees decay and
enrich the soil with nutrients, and new plants use that soil to grow — as Ajji
explained during the forest walk.

In-text Questions — Page 220
11.5 — Rocks and the minerals in them

Q1 What are rocks made up of?

Rocks are made up of minerals. A rock is not one single substance — it is a natural mixture of
one or more minerals packed together.

ROCK WHERE YOU SEE IT IN INDIA WHAT IT IS USED FOR

Granite Karnataka, Telangana, Rajasthan, Tamil Floors, kitchen platforms, temple pillars,
Nadu monuments

Sandstone Dholpur and Jodhpur (Rajasthan) Buildings — the Red Fort and Fatehpur Sikri are
of red sandstone

Marble Makrana (Rajasthan) Statues, floors, table tops — the Taj Mahal is of
Makrana marble

Slate Kangra (Himachal Pradesh), Markapur Roofing (Fig. 11.6), writing slates, flooring
(Andhra Pradesh)

Laterite Kerala, coastal Karnataka, Goa, Cut into blocks and used like bricks (Fig. 11.7)
Konkan, Odisha

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Class 6 Science Chapter 11 Nature’s Treasures
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c om
What we get out of minerals:
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Important metals such as aluminium, gold, copper and iron are extracted efrom
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Why they must be used responsibly:
s emit takes thousands to millions of years to form
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renewable.
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In-text Questions — Page g l ase
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11.5 / 11.6 — Transporting minerals, and different fuels

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MEANS OF WHAT IT CARRIES FUEL USED

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TRANSPORT

Trucks and dumpers
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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Why the book asks this here: it is the bridge to the next section. Most vehicles we
use for transportation run on fossil fuels — so even a truckload of stone costs us
some coal or petroleum. Two natural resources are being used, not one.

Q2 Surya, why do different types of vehicles go to different filling stations?

Because different vehicles run on different fuels, and a filling station stocks only the fuels it is
set up for.

VEHICLE USUAL FUEL WHERE IT COMES FROM

Scooter, motorcycle, most cars Petrol Obtained from petroleum

Truck, bus, tractor, most SUVs Diesel Obtained from petroleum

Many autos, city buses and taxis CNG (Compressed Natural Natural gas — a cleaner fuel than petrol
Gas) or diesel

Electric scooters, e-rickshaws, Electricity Charged at a charging station; give out
electric cars no smoke

Why one fuel cannot replace another: an engine is built for a particular fuel. Petrol
burns easily with a spark, diesel burns under strong squeezing, and CNG is stored as
a gas under pressure in a strong cylinder. Putting the wrong fuel in a vehicle
damages the engine — which is why the pumps and even the nozzles are kept
separate.

Did you know? Petrol, diesel and kerosene are all obtained from petroleum.
Petroleum, natural gas and coal together are called fossil fuels.

Activity 11.5: Let us conduct a survey — Page 222

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.6 Fossil Fuels — Table 11.3 Types of vehicles and fuels used

ACTIVITY

Q1 Conduct a survey of vehicles in your neighbourhood. Which types of vehicles are
there? What types of fuels do they use? Record the information that you collect in
Table 11.3.

TABLE 11.3: TYPES OF VEHICLES AND FUELS USED

TYPE OF VEHICLE TYPE OF FUEL USED

Table 11.3 as printed on page 222 — both columns are blank for your survey.

Stand safely near a road or in your colony for fifteen minutes and note down every vehicle you
see. A filled Table 11.3 looks like this.

TYPE OF VEHICLE TYPE OF FUEL USED

Scooter / motorcycle Petrol

Car (small, family car) Petrol or diesel; some run on CNG

Auto-rickshaw CNG or petrol

School bus / city bus Diesel or CNG

Truck / tempo / tractor Diesel

E-rickshaw / electric scooter Electricity (battery)

Bicycle, bullock cart, hand cart No fuel — muscle power

Train (in some places) Electricity, or diesel on unelectrified lines

Tip: Add a third column of your own — “how many did I count?” Then you can say
which fuel is used by the most vehicles in your locality, not just which fuels exist.

Page 31 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q2 What are the most common types of fuels used?

Petrol and diesel are the two most widely used fuels for vehicles. In most Indian surveys
petrol comes first, because two-wheelers outnumber every other vehicle.

Petrol, diesel and kerosene ← obtained from petroleum

Petroleum + natural gas + coal = fossil fuels

Petrol — scooters, motorcycles, most cars.
Diesel — buses, trucks, tractors, generators.
CNG (Compressed Natural Gas) — autos, taxis and city buses; it is a cleaner fuel than
petrol or diesel.
Electricity — a growing number of e-rickshaws, scooters and cars, which release no smoke
at all.

Why this survey matters: almost every vehicle on the list burns a fossil fuel. Fossil
fuels are found in limited quantities and take millions of years to form — so the
more the survey list grows, the sooner the stock runs out and the more the air is
polluted.

In-text Questions — Page 222
11.6 — Coal and other fuel resources of India

Q1 Coal is mainly used for the production of electricity. It is found in several parts of
India. Find out the major coal-producing states and mark them in a map of India.

Coal is found in a broad belt across eastern and central India. Take an outline map of India,
shade these states and write the name of the coalfield beside each.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

STATE IMPORTANT COALFIELDS NOTE

Chhattisgarh Korba, Raigarh, Chirimiri Among the top producers in the country

Odisha Talcher, Ib Valley Huge reserves; feeds many power plants

Jharkhand Jharia, Bokaro, North Karanpura, Jharia gives the best coking coal, used in steel
Giridih plants

Madhya Pradesh Singrauli, Sohagpur, Pench–Kanhan Singrauli is called India’s “energy capital”

Telangana Singareni (Ramagundam, The main coal source of south India
Kothagudem)

West Bengal Raniganj India’s oldest coalfield — mining began in
1774

Maharashtra Chandrapur, Wardha valley Supplies power plants of western India

Tamil Nadu Neyveli Lignite (brown coal), not black coal

Assam and Makum, Jaintia hills Small but old fields of the north-east
Meghalaya

While you are at it, mark the other fuel resources too:

Petroleum — Mumbai High (offshore Maharashtra), Ankleshwar and Kalol (Gujarat), Digboi
and Naharkatiya (Assam), Barmer (Rajasthan).
Natural gas — the Krishna–Godavari basin (Andhra Pradesh), Tripura, Gujarat and Assam.

Why coal is in the east: these coal seams formed from plants that were buried in
ancient river valleys of the Damodar, Mahanadi, Son and Godavari basins millions of
years ago. That is also why India’s big steel plants — Bokaro, Rourkela, Bhilai,
Durgapur, Jamshedpur — were built close to the coal and the iron ore.

Tip for the map: use one colour for coal, another for petroleum and a third for
natural gas, and add a small key in the corner. Do not forget to write “Not to scale”.

In-text Questions — Page 223

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Class 6 Science Chapter 11 Nature’s Treasures
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11.6 — Conserving fossil fuels
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Q1
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Let us do our bit to conserve the fossil fuels by— Walking or cycling to nearby
m a g
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places. Using public transport. Suggest some more ways.

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The book gives two. Here are more, grouped by where the saving happens.
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WHERE WHAT TO DO
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On the road Share a car or take the school bus (car-pooling); switch off the engine at a red light; keep tyres

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Prefer CNG or electric vehicles; use the metro or train for long journeys instead of many separate

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vehicle cars

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a s
and a solar water heater on sunny days; light the gas only after everything is ready

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Save Most of our electricity comes from coal — so switching off fans and lights, and using LED bulbs,
electricity saves coal
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Use other Solar panels, wind energy, biogas from cattle dung, hydroelectricity
sources
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of them if we keep using them the way we do now. And when they burn, smoke and
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In-text Questions — Page 224
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11.8 Resources

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Q1 Can you list some alternatives for reducing air pollution?
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Bhoomi and Surya could smell the difference the moment they reached the city — very few
trees, and smoke from the vehicles. Here is what can be done about it.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

ALTERNATIVE HOW IT REDUCES AIR POLLUTION

Electric vehicles They do not release any smoke at all, as Amma explains in the
story

CNG buses, autos and cars CNG is a cleaner fuel than petrol or diesel

Public transport, cycling and walking One bus replaces forty cars’ worth of smoke

Solar and wind electricity No coal burnt, so no smoke from the power plant

LPG, natural gas or a solar cooker at Far less smoke than coal, firewood or dung cakes
home

Planting more trees Trees take in carbon dioxide, trap dust and cool the air

Stop burning garbage and crop stubble Compost the waste instead of setting it on fire

Cover construction sites and sprinkle Keeps dust from rising into the air
water

Filters and chimneys in factories Trap smoke and ash before they reach the open air

Why the village air felt better: the village has many trees and few vehicles, so the
air is fresh and cooler. A city has the opposite — that is not bad luck, it is the result of
choices, and different choices can change it back.

Activity 11.6: Let us make a list of natural resources used — Page 225

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

11.8 — Table 11.4 Natural resources used

ACTIVITY

Q1 Make a list of activities you do in your daily life and write down the natural
resources used directly or indirectly for each activity. In Table 11.4, some items are
already filled in. Using them as a guide, fill the remaining blank rows.

TABLE 11.4: NATURAL RESOURCES USED

ACTIVITY NATURAL RESOURCE

Washing clothes Water

Making clay toys

Collecting firewood

Making kites

Having breakfast

Table 11.4 as printed on page 225 — the first row is filled in as an example.

Table 11.4 completed. Notice how almost every row ends up using more than one resource.

Page 36 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

ACTIVITY NATURAL RESOURCE

Washing clothes Water (given)

Making clay toys Soil (clay), water, energy from the Sun to dry them

Collecting firewood Forest (wood from trees)

Making kites Forest (paper from wood), bamboo, air to fly them

Having breakfast Soil, water and sunlight to grow the grain; plants and animals for food; natural
gas or firewood to cook it

Drinking a glass of water Water from a river, well or rain

Going to school by bus Fossil fuels — diesel or CNG; minerals for the metal body

Reading and writing Forest (paper), minerals (graphite in the pencil), petroleum (plastic pen)

Switching on a fan or Coal, water or wind used to generate the electricity; minerals in the wires
light

Breathing and playing Air, and sunlight
outdoors

Building a house Rocks, sand, soil for bricks, water, wood, iron from minerals

What the list proves: we cannot do anything in a day without natural resources.
That is exactly why the chapter ends by saying we must conserve them and use
them responsibly, so that we meet our present needs while also saving for the future
without harming the environment.

Compare with a friend: your lists will not match — someone will have written
“drawing a rangoli” (soil, colours from minerals) or “playing cricket” (wood for the
bat, rubber for the ball). Every new activity adds a new resource.

Let us enhance our learning — Pages 227 – 229

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Chapter exercise

Q1 Fig. 11.9 shows items related to natural resources. Match them with their jumbled
up names. Make another table and write the names of these resources. Classify
these resources as renewable or non-renewable. (Jumbled names: ocrk, refost,
ndiw, atwre)

FIG. 11.9: NATURAL RESOURCES

ITEM JUMBLED UP NAME

(picture not printed in this reprint of the book) ocrk

(picture not printed in this reprint of the book) refost

(picture not printed in this reprint of the book) ndiw

atwre

Fig. 11.9 as printed on page 227. In this reprint only the fourth item picture is actually
printed; the first three item boxes come out blank in the book's own PDF.

Step 1 — unjumble the names.

Page 38 of 61

as e
Class 6 Science Chapter 11 Nature’s Treasures
a g l AglaSem · NCERT Solutions

co m
m.
JUMBLED UP NAME CORRECT NAME

m as e
ocrk
.co
rock
a g l
se m
g l a
a
refost forest

ndiw wind

co m water
m . ag
se
atwre

l a
agits name. In Fig. 11.9 the picture in the last row is a rock, so
Step 2 — match each picture with
it matches ocrk. Match the remaining three pictures in your book — trees growing together,

co m
m.
something being blown or turned by moving air, and flowing or stored water — with refost, ndiw

ase
comnew table, with the classification.
and atwre.
Step 3 —.the
a g l
a s em
aglRESOURCE RENEWABLE / NON- REASON

s
RENEWABLE
m a
m.coTakes thousands to millions of years to form; once quarried it is agl
se
Rock Non-renewable

g l a not replaced in our lifetime

Forest Renewable
a Trees grow again from seeds and are restored by nature —

com
provided they are given enough time

.
a s em does not use it up
com agl
Wind Renewable Air keeps moving; using it in a windmill

m .
as e
Water

agl
Renewable Nature renews it through the water cycle — evaporation, clouds
and rain

se m
com g l a
. a
Careful: “renewable” does not mean “unlimited”. A forest is renewable only if it is cut
m
ase
slowly enough to grow back, and water is renewable only if we do not pollute it or

agl
pump out groundwater faster than the rain replaces it.

co m
m .
m as e
.co a g l
se m
g l a
a c
m .
m a s e
e m . co agl
g l as
a

co m
m .
m as e
.co


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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q2 State whether the following statements are True [T] or False [F]. If False, correct
them. (i) Nature has all the resources to meet human needs. (ii) Machines are a
resource found in nature. (iii) Natural gas is a non-renewable resource. (iv) Air is a
renewable resource.

STATEMENT T/F CORRECTED STATEMENT / REASON

(i) Nature has all the True Nature provides everything we need to survive — air, water, sunlight, soil,
resources to meet human [T] food, forests, minerals and fuels. As Gandhiji said, “Earth provides enough
needs. to satisfy every man’s need but not for every man’s greed.”

(ii) Machines are a False Corrected: Machines are human-made resources. They are made by
resource found in nature. [F] people using natural resources such as minerals and fossil fuels.

(iii) Natural gas is a non- True It is a fossil fuel. It took millions of years to form, is present in limited
renewable resource. [T] quantity, and is not replenished within a reasonable period.

(iv) Air is a renewable True Nature keeps renewing it — plants release oxygen, and the winds and the
resource. [T] water cycle keep mixing and cleaning it.

The idea being tested: the difference between what nature gives (natural
resources) and what we build out of it (human-made resources), and the difference
between resources nature can restore quickly and those it cannot.

Q3 Fill in the blanks using the most appropriate option— (i) A fuel that is commonly
used in two wheelers like scooters or bikes is......... (a) Kerosene (b) Petrol (c) Diesel
(d) LPG. (ii) An example of a renewable resource is .................. (a) Coal (b) Water (c)
Natural gas (d) Petrol

(i) A fuel that is commonly used in two wheelers like scooters or bikes is (b) Petrol.

(a) Kerosene — used in lamps and stoves, not in two-wheeler engines.
(c) Diesel — used in trucks, buses and tractors, which have a different kind of engine.
(d) LPG — a cooking gas; a few vehicles use gas, but as CNG, not as the usual two-wheeler
fuel.

(ii) An example of a renewable resource is (b) Water.

(a) Coal, (c) Natural gas and (d) Petrol (from petroleum) are all fossil fuels — non-
renewable.

Page 40 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Water is renewed by nature through the water cycle, so it is renewable.

Tip: in questions like (ii), first ask “is it a fossil fuel or a mineral?” If yes, it is non-
renewable. Air, water, forests, sunlight and wind are the usual renewable answers.

Q4 Classify the following as renewable or non-renewable resources—coal, natural gas,
forests and minerals.

RESOURCE TYPE WHY

Coal Non- A fossil fuel formed over millions of years from buried plant remains; limited in
renewable quantity and exhausted once used

Natural Non- Also a fossil fuel, formed with petroleum deep inside the Earth over millions of
gas renewable years

Forests Renewable New trees grow from seeds, so nature restores a forest — but only if it is given
enough time

Minerals Non- Formed inside rocks over an enormous time; the deposits are limited and are not
renewable replenished

Renewable: forests

Non-renewable: coal, natural gas, minerals

Q5 Why do we say that petroleum is a non-renewable resource?

Because it takes millions of years to form, is present in limited quantity, and is not
replenished within a reasonable period of time — once used, it is gone.

How it formed: petroleum was formed from the remains of microorganisms and plants
that got buried deep inside the Earth long ago and were slowly changed into petroleum,
natural gas and coal.
How long it took: millions of years — not years or centuries.
How much there is: it is found only in certain places and in limited quantity — in India at
Mumbai High, in Gujarat, Assam and Barmer in Rajasthan.

Page 41 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

What happens when we use it: the petrol or diesel is burnt and turns into smoke and
gases. Nothing is left behind that can become petroleum again.

Formed in millions of years → used up in a few hundred years

Not restored in a reasonable time = non-renewable

Compare it with a forest: a felled tree can be replaced in twenty or thirty years —
within a human lifetime, so a forest is renewable. Nobody can wait a million years for
the petrol tank to refill, so petroleum is not.

Q6 It is difficult to regrow forests. Justify this statement.

A forest is not just a crowd of trees — it is a whole community of plants, animals, soil and
micro-organisms built up over a very long time. Trees can be planted; a forest has to grow.

Trees take decades. A sal, teak or deodar tree needs 30 to 60 years to reach full size. It takes
many years to grow a new forest or restore a lost one.
The soil is lost first. Once the trees are gone, the roots no longer hold the soil, and rain
washes the fertile topsoil away. New saplings then have poor soil to grow in.
The undergrowth and humus are gone. The layer of decaying leaves that enriches the soil
takes years to build up again.
The animals leave. Birds, bats, bees and insects that pollinate flowers and scatter seeds
move away, so natural regrowth becomes slow. Ajji’s village leaves fallen fruit for animals
precisely so that their droppings sow new trees.
Only a few species get replanted. A natural forest has hundreds of kinds of plants; a
plantation usually has one or two, so the variety of life is not restored.
Weeds take over the cleared land and choke the new saplings.

The correct conclusion: since regrowth is so slow, we must preserve and use
forests responsibly so that they get enough time to regenerate — protecting an
existing forest is far easier than making a new one.

Did you know? This is exactly the idea behind the Chipko movement, which started
in the early 1970s in Uttarakhand (then part of Uttar Pradesh). Local women
encircled and hugged the trees to protect them from being felled — because they
knew the forest would not come back in their lifetime.

Page 42 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q7 Make a list of five daily activities in which you use natural resources. Suggest ways
by which you can reduce their use.

DAILY ACTIVITY NATURAL HOW I CAN REDUCE THEIR USE
RESOURCES USED

1. Brushing teeth Water Use a mug of water while brushing; bathe with a bucket
and bathing instead of a shower; report leaking taps

2. Travelling to Fossil fuels — petrol, Walk or cycle if the school is near; take the school bus; share
school diesel or CNG a ride with neighbours

3. Cooking and Natural gas or firewood, Use a pressure cooker with the lid on; cook only as much as
eating a meal water, soil, sunlight will be eaten; never waste food, because wasted food wastes
all the resources that grew it

4. Using lights, Coal (most electricity Switch off when leaving the room; use LED bulbs; open the
fan and TV comes from coal) windows for daylight; use solar power where possible

5. Writing in Forests (paper), minerals, Use both sides of the sheet; finish old notebooks; use a
notebooks petroleum (plastic) refillable pen; give old books to juniors and recycle waste
paper

The rule behind every suggestion: reduce, reuse, recycle. Reducing comes first
because a resource never used is a resource fully saved.

Q8 List four activities that are possible due to the presence of air.

Four (with more to spare):

1. Breathing and respiration — we and almost all living beings take in oxygen from the air;
without it we cannot survive even a few minutes.
2. Burning of fuel — the gas stove, the chulha and every vehicle engine need the oxygen of
the air to burn fuel and give heat.
3. Generating electricity from wind — moving air turns the wings of a windmill, as at
Muppandal in Tamil Nadu and the Jaisalmer Wind Park in Rajasthan; the same wind turns a
firki.
4. Drying of wet clothes and grain — moving air carries away the water vapour, so wet things
dry faster on a windy day.

Page 43 of 61

ase
Class 6 Science Chapter 11 Nature’s Treasures
a g l AglaSem · NCERT Solutions

Other correct answers:
co m
e m.
mwith the wind, and winnowing grain to separate the husk. as
Flying a kite, and the flying of birds and aeroplanes.

. c o a g l
m
Sailing a boat

as e
l
Speaking and hearing — sound travels through air.
g
a Pollination and scattering of seeds by the wind.

. com
How to spot such activities: ask “would this still work in an empty space with no
ag
a s emjob.
air?” If the answer is no, air is doing the

agl

co m
em.
How can you contribute towards enhancing the green cover of your locality? Make

as
Q9

m l
.co
a list of actions to be taken.
a g
se m
g l a
a Actions I can take (in order of what a Class 6 student can actually do):

om a s
. c agl
1. Plant saplings at home, in school and along the colony road — and choose native trees such

s e m
a
as neem, peepal, banyan, gulmohar, amla, jamun, mango and moringa rather than only

agl
decorative ones.
2. Look after them, not just plant them — water each sapling, put a tree guard around it,
and add dry leaves at the base. A sapling that dies is not green cover.
com
m .
se
3. Adopt a tree — let each child in the class take charge of one tree for the whole year and

o m g l a
.c a kitchen garden — tulsi, curry leaf, mint, chillies and tomatoes
keep a record of its growth.
4. m
e a
s
Grow in pots on the balcony

ag la or terrace.
m
5. Make compost from kitchen and garden waste and use it instead of buying fertiliser.

om teacher.
6. Celebrate Van Mahotsav — the week-long forest festival held across the country in July —
l a se
and organise a plantation drive with.cyour a g
7. Protect what already existsa— s mnot pluck branches or carve names on trunks; report
edo
agl permission; save the old trees of the neighbourhood.
anyone cutting a tree without
8. Spread the word — posters, a wall magazine, a street play, and gifting saplings on birthdays
instead of plastic gifts.
. com
m your street has, so the
9. Join the school eco-club and keep a simple survey of how many etrees
s
o m
cincrease gl a
. a
em
can be measured.

as
agl c
.
Why green cover matters: trees give shade and oxygen, take in carbon dioxide,
hold the soil with their roots, help bring rain, and are home to birds and insects.
s e m
m a
. co agl
Increasing the green cover is the aim of Van Mahotsav itself.
em
g l as
a

com
m .
m ase
.co


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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q10 In the given illustration, we see that food is being cooked. Answer the following
questions— (i) What type of energy is being used for cooking? (ii) Name one
benefit and one drawback of using this type of energy for cooking.

The illustration printed with this question on page 228 — redrawn sketch.

The picture shows a large shining dish facing the sky with a vessel placed in front of it, outside a
village hut — this is a solar cooker (a dish-type solar cooker).
(i) The energy used is solar energy — heat and light from the Sun. The curved dish gathers
the Sun’s rays and concentrates them on the vessel, which becomes hot enough to cook the
food. No fuel is burnt at all.
(ii) One benefit and one drawback

BENEFIT DRAWBACK

It is free and clean — no firewood, coal or LPG is It works only in bright sunshine — no cooking on a
needed, so there is no smoke and no air pollution, and a cloudy day, in the rains or after sunset, and it is slower
non-renewable fuel is saved than a gas stove

More benefits: no fuel bill, no danger of fire or gas leak, the food does not burn, and it keeps its
nutrients.
More drawbacks: the cooker is costly to buy, needs open space, must be turned every hour to
face the Sun, and cannot be used for frying or making chapatis.

Page 45 of 61

Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Why this matters: solar energy is renewable — the Sun keeps supplying it. Every
meal cooked in a solar cooker is LPG or firewood saved, so this one device links three
ideas of the chapter: energy from the Sun, conserving fossil fuels and reducing air
pollution.

Q11 Cutting down trees on a large scale impacts the quality of the soil. Why do you
think it is so?

Because the trees are what keep the soil in place and keep it fertile. Take them away and
the soil is damaged in four different ways.

1. The soil is washed away (erosion). The roots of plants hold on to the soil and prevent it
from being washed away. With no roots, rain water carries the fertile topsoil into streams
and rivers, and wind blows away the dry surface.
2. The soil loses its nutrients. Leaves that fall from trees decay and enrich the soil with
nutrients, which new plants then use. No trees means no leaf-fall, no decay, and a soil that
grows poorer every year.
3. The soil dries out and hardens. Without the shade of the trees, the Sun beats directly on
the ground; moisture evaporates, and the soil bakes hard and cracks.
4. The life inside the soil dies out. Earthworms — natural agents that turn and loosen the soil
— insects and tiny organisms need moisture and dead leaves. Without them the soil stops
being loosened and mixed.

No trees → no roots → topsoil washed away

No leaf-fall → no humus → soil loses nutrients

No shade → soil dries and hardens → barren land

Why it cannot be quickly repaired: soil is formed by the disintegration of rocks
over thousands of years. What the rain removes in one monsoon cannot be
replaced in a lifetime — this is why soil is counted among the non-renewable
resources.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q12 Explain two ways in which human activities pollute the air. Propose one action
which can help in reducing air pollution.

Two ways human activities pollute the air:

1. Burning fossil fuels in vehicles. When petrol and diesel burn in engines, smoke and
carbon dioxide are produced. Over-dependence on fossil fuels for transportation has
caused large-scale air pollution — which is exactly what Bhoomi and Surya smell when they
reach the city.
2. Burning fuels in factories and power plants, and burning waste. Coal burnt to produce
electricity, and the smoke from brick kilns, chimneys, burning garbage and crop stubble, fill
the air with soot, ash and harmful gases. Cooking on coal, wood and dung cakes pollutes the
air inside homes too.

Other ways: dust from construction, mining and quarrying; chemical fumes and pesticide
sprays; burning of plastic waste.
One action to reduce air pollution:

Use public transport, or walk and cycle for short distances, instead of a separate vehicle

for each person.

One bus carries as many people as forty scooters, so it produces a fraction of the smoke per
person. Other good actions: shift to CNG or electric vehicles, use LPG or a solar cooker at
home instead of coal or dung cakes, switch off the engine at red lights, and plant more trees,
which take in carbon dioxide and trap dust.

Why cleaner air is urgent: polluted air is breathed in by everyone — children,
elders and animals alike. Unlike a polluted pond, you cannot walk away from
polluted air.

Q13 A family uses solar panels to generate electricity, a gas stove to cook food and a
windmill for pumping water from a well. What would happen if there were no
sunlight for a week?

Take the three devices one by one.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

DEVICE WHAT HAPPENS WHY
IN THAT WEEK

Solar Stop working almost Solar panels capture the Sun’s energy to produce electricity. With no sunlight
panels completely there is nothing to capture — lights, fan and TV will not run, and the stored
battery charge will be used up in a day or two.

Gas stove Keeps working It burns natural gas or LPG, which is already stored in a cylinder or pipeline.
normally It does not need sunlight, so the family can still cook.

Windmill Keeps working as It is turned by wind, not by sunlight, so water can still be pumped from the
long as the wind well.
blows

The rest of the household would also feel it: clothes would not dry, food and chillies could not
be sun-dried, a solar water heater would give no hot water, plants would grow poorly, and the
days would be dark and cold.

A deeper point worth writing: the wind itself is created because the Sun heats
different parts of the Earth unequally. So if the Sun stayed hidden for a very long
time, even the winds would weaken — and the Sun would turn out to be behind two
of the three devices, not one. This is why the Sun is called the main source of
energy on Earth.

Tip for the exam: answer device by device — say clearly which one stops, which two
continue, and give the reason for each. That is what the question is checking.

Q14 Fill up the blanks using the following terms— (fossil fuels, forest, air, petroleum,
coal, water and non-renewable resource). [Flow chart: Natural Resources → .........
and Renewable Resources; under the first, ......... → ........., Natural gas, .........; under
Renewable Resources, three blanks]

The completed chart:

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Class 6 Science Chapter 11 Nature’s Treasures
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co m
e m.
com l as
Natural

.
Resources
a g
m
ase
agl Non-renewable
resource
Renewable
Resources

co m
e m . ag
l as
Fossil fuels Air Water Forest

a g
Natural
co m
m.
Coal Petroleum
gas

o m l a se
m .cresources split into non-renewable and renewable. “Natural gas”agwas already printed in the
se
Natural

g l a chart; the shaded boxes are the seven blanks.

a
m a s
.co agl
POSITION IN THE CHART ANSWER

se m
Left circle under “Natural Resources”
g l a Non-renewable resource

Box below it
a Fossil fuels

com
First box in the bottom-left row Coal
m .
m as e
.co a g l
m
Third box in the bottom-left row Petroleum

a s eThree
a gl boxes under “Renewable Resources” Air, Water, Forest

se m
com g l a
. a
How to be sure: “Natural gas” is already printed in the middle box of the bottom
m
ase
row, and coal, petroleum and natural gas are precisely the three fossil fuels. So that

a gl
whole branch has to be the non-renewable one, and the three remaining words —
air, water and forest — are exactly the renewable examples given in the chapter.

co m
m .
o m l a se
m .c There is an increasing demand of trees to meet theagrequirements of industries and
se
Q15

a
agl
for housing. Therefore, trees are being felled. Is it justified? Discuss and prepare a

.c
brief report.

s e m
m a
m . co agl
l a se
Position: the demand is real, but felling natural forests on a large scale to meet it is not
justified. The need can a
begmet in ways that do not destroy forests.

co m
m .
m ase
.co


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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Sample report — Should trees be felled to meet the demand of industry and housing?
1. The demand is genuine. Wood is needed for furniture, doors, windows and
scaffolding; paper is needed for books and packing; land is needed for houses as
families grow. Lakhs of people also earn their living from these industries.
2. What large-scale felling costs us. The forest cover has been decreasing over the
years, mainly because of human activities like large-scale cutting of trees. When a
forest goes: fertile topsoil is washed away, the land grows barren, wells dry up while
floods get worse, wild animals and birds lose their food and shelter, the air gets
more carbon dioxide and less oxygen, and forest-dwelling families lose their
livelihood. It takes many years to grow a new forest or restore a lost one — the loss
is not repaired in our lifetime.
3. Therefore my conclusion. Cutting a few trees under a plan, and replanting more
than were cut, is acceptable. Clearing a natural forest is not — we are trading
something irreplaceable for something we could have got another way.
4. What should be done instead.

Grow wood as a crop — social forestry and agroforestry: eucalyptus, poplar,
bamboo and casuarina on farm bunds and waste land, instead of cutting natural
forest.
Use bamboo, which regrows in three to four years, and engineered board made
from wood waste.
Recycle paper and print on both sides; every tonne of recycled paper saves many
trees.
Build with brick, stone, steel and cement where wood is not essential; repair
and reuse old furniture.
Replant at least five saplings for every tree felled, and look after them until they
are established.
Support Van Mahotsav, protect sacred groves, and follow the example of the
Chipko movement of the early 1970s in Uttarakhand, where local women
hugged the trees to save them.

5. In one line. We must preserve and use forests responsibly so that they get
enough time to regenerate — meeting today’s needs without robbing tomorrow’s.

How to argue this well in class: do not simply say “cutting trees is bad”. Accept that
the demand exists, then show a better way of meeting it. That is what makes a
report convincing.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Q16 Propose a plan to use less water in your school. What steps would you take to
make this plan happen and how would it help the environment?

Sample plan: “Save Every Drop” — a water plan for our school
Step 1 — Find out where water is used and wasted (Week 1). Form a Water Club
of two students from each class. Walk through the school with a checklist and note
every tap, cooler, tank and toilet. Count how many taps drip, how many do not close
fully, and whether the overhead tank overflows. Draw a simple map of the school
marking each water point.
Step 2 — Fix what is broken (Week 2). Give the list to the Principal. Get washers
changed in leaking taps, broken pipes repaired and a float valve fitted in the
overhead tank so it stops filling on its own.
Step 3 — Change how we use water (Week 3 onwards).

Put a small painted sign above every tap: “Close me after use.”
Fit push-taps or half-open the main valve so less water gushes out at the wash
basins.
Keep a drum of used RO water and hand-wash water for cleaning the floors and
the courtyard.
Water the school garden early in the morning with a can, not a hose, and spread
dry leaves around the plants.
Ask each class to bring a water bottle from home, so less is drawn and spilled at
the cooler.

Step 4 — Put water back (this monsoon). Lead the rainwater from the school roof
through a pipe into a storage tank and a recharge pit near the playground. Keep
some ground unpaved so rain can soak in.
Step 5 — Measure and report (every month). Note the meter reading or the
number of tanker loads each month and put a chart on the notice board. Give a
“Blue Star” to the cleanest, most water-wise class each month.
Step 6 — Spread it. Morning-assembly announcements, posters, a street play on 22
March (World Water Day), and a letter home so families follow the same rules.

How this helps the environment:

Less water drawn from the borewell or the municipal supply means less groundwater
pumped out, so the water table falls more slowly.
Rainwater harvesting recharges the ground instead of letting rain run off into drains.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

Pumping water uses electricity, most of which comes from coal — so saving water also
saves coal and cuts air pollution.
More water is left in the rivers and ponds for farmers, animals and the fish that live there.
Students carry the habit home, so the saving multiplies across the whole neighbourhood.

Why a plan needs steps and numbers: “we will save water” is a wish. “We fixed 11
dripping taps and cut one tanker a month” is a plan that can be checked — and that
is what makes it happen.

Learning further — Pages 229 & 230
Projects and further exploration

PROJECT WORK

Q1 Rainwater harvesting is an age-old practice in India. Find out some of the
traditional rainwater harvesting techniques being used in your state or in other
parts of the country.

Every region of India invented a method that suited its own rainfall, soil and slope. Find the one
from your state in this table and then ask an elder about it.

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

TECHNIQUE STATE / REGION HOW IT WORKS

Bawadi / Baoli Rajasthan Deep stepped well; stores rainwater and water seeping
(stepwell) from nearby lakes, ponds and rivers — Toorji ka Jhalra,
Jodhpur (Fig. 11.4b); Chand Baori, Abhaneri

Vav Gujarat Stepwell — Rani ki Vav, Patan (a World Heritage Site) and
Adalaj ni Vav

Tanka and Kund Western Rajasthan Underground tank in a courtyard, fed by a sloping
catchment; keeps drinking water cool

Johad and Rajasthan (Alwar, Earthen check dam across a slope; embankment that holds
Khadin Jaisalmer) runoff on farmland until the crop is sown

Virda Kutch, Gujarat Shallow wells dug in low ground where sweet rainwater
floats above the salty water

Ahar–Pyne Bihar (Magadh region) Diversion channels (pyne) feed a reservoir with three
embankments (ahar)

Eri (tanks) Tamil Nadu Chains of village tanks; the overflow of one fills the next, so
no rain is lost

Kere, Kalyani, Karnataka Village tanks and stepped temple tanks
Pushkarni

Phad and Maharashtra (Nashik, A stone weir on a stream diverts water into canals serving
Bandhara Dhule) blocks of fields

Haveli system Madhya Pradesh Rain is held on the field itself by low bunds through the
(Bundelkhand) monsoon

Katas, Mundas, Odisha, Jharkhand Earthen tanks on the upper part of a slope for the fields
Bandhas below

Kuhl / Kul, Himachal Pradesh, Small stone-lined canals from a glacier stream; a naula is a
Naula, Guhl Jammu, Uttarakhand stepped tank built over a spring

Zing Ladakh Tank that collects glacier melt-water during the day for use
in the evening

Bamboo drip Meghalaya Split bamboo pipes carry spring water down the hill, drop
irrigation by drop, to betel and pepper plants

Zabo (Ruza) Nagaland Rain caught on a hilltop, passed through cattle yards and
on to terraced fields and fish ponds

Surangam Kerala, Kasaragod A tunnel cut into a laterite hillside that taps water seeping
through the rock

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TECHNIQUE STATE / REGION HOW IT WORKS

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Cheruvu, Kunta
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Village tanks and small ponds, revived under the Mission

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How to present the project: pick one method, draw a labelled sketch of it, write where it is
used, how it is built, who maintains it, and whether it still works today. Add a photograph or a

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rubbing from a plaque if there is such a structure near you.

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Modern version: rooftop rainwater harvesting (Fig. 11.4a) is the same idea with
pipes — rain from the roof goes into a filter, then into a storage tank or a recharge
pit. Many Indian cities now make it compulsory for new buildings.
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Investigate the effect of air pollution on human health by interacting with your
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elders or community members and identify the main sources of air pollution in your

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local area. Based on your findings, suggest two practical steps that your school or
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community could take to help reduce air pollution.

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Part A — How to carry out the investigation

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1. Make a short questionnaire (6–8 questions) — for example: Has the air here changed in the
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last twenty years? Do you or anyone at home get cough, breathlessness, watering eyes or

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3. Observe for yourself — wipe a white cloth on a window sill facing the road and another on

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an inner window, and compare the dust.
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Part B — What such an investigation usually finds

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

EFFECT ON HEALTH REPORTED MAIN LOCAL SOURCES IDENTIFIED

Cough, sore throat and repeated colds Smoke from vehicles on the main road

Breathlessness and asthma, worse in winter Burning of garbage, dry leaves and plastic

Watering, burning eyes Dust from construction sites and unpaved roads

Headache and tiredness Diesel generators, brick kilns or a nearby factory chimney

Smoky kitchens, eye irritation in elderly women Cooking on firewood, coal or dung cakes

Cough after the harvest season Burning of crop stubble in the fields

Part C — Two practical steps (choose the two that fit your findings)

1. A “No-vehicle day” and a walking bus for the school. One day a week, everyone within
two kilometres walks or cycles; others share rides. Ask parents not to keep engines running
in the pick-up line — a “switch off your engine” board at the gate.
2. A “no burning, only composting” rule for the school and colony. Put up two bins,
compost the dry leaves and kitchen waste in a pit instead of burning them, and hand the
compost to the school garden. Add a plantation drive along the boundary wall, since trees
trap dust and take in carbon dioxide.

Why the interviews matter: numbers from a book are distant; hearing a neighbour
say “I could see the hills from here as a child” makes the change real, and it teaches
you that evidence can also be collected by asking, not only by measuring.

Q3 Prepare a list of the names and uses of important minerals and rocks that are used
in your village/town/city for various purposes.

How to do it: walk around your locality with a notebook. Look at the floor of your school, the
walls of a temple, the kerb stones, the road metal, a construction site and a hardware shop. Ask
the mason or the shopkeeper what each material is and where it comes from.
Rocks — what to look for

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

ROCK WHERE YOU WILL SEE IT WHERE IT COMES FROM IN INDIA

Granite Kitchen platforms, floor slabs, temple Karnataka, Telangana, Tamil Nadu,
pillars, monuments Rajasthan

Marble Floors, statues, temple work, table tops Makrana and Kishangarh (Rajasthan)

Sandstone Building walls, carved brackets, paving Dholpur and Jodhpur (Rajasthan)

Slate Roofing (Fig. 11.6), flooring, writing slates Kangra (Himachal Pradesh), Markapur
(Andhra Pradesh)

Laterite Cut into blocks and used like bricks (Fig. Kerala, coastal Karnataka, Goa, Konkan,
11.7) Odisha

Limestone Raw material of cement; chuna for Rajasthan, Madhya Pradesh, Andhra
whitewash Pradesh, Gujarat

Basalt / trap Road metal, railway ballast, building Deccan plateau — Maharashtra, Madhya
rock stone Pradesh

Gravel and Concrete, plaster, mortar River beds and quarries near every town
sand

Minerals — what they become

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

MINERAL / USED FOR MINED MAINLY IN
METAL

Iron ore → iron Grills, gates, rods for building, tools, Odisha, Chhattisgarh (Bailadila), Jharkhand,
and steel vehicles, railway lines Karnataka, Goa

Bauxite → Vessels, window frames, foil, Odisha (Panchpatmali), Jharkhand, Gujarat,
aluminium aeroplane bodies, electric wires Chhattisgarh

Copper ore → Electrical wiring, utensils, temple Khetri (Rajasthan), Singhbhum (Jharkhand),
copper bells Malanjkhand (Madhya Pradesh)

Gold and silver Jewellery, and tiny contacts inside Kolar and Hutti (Karnataka)
mobile phones

Manganese Making strong steel, dry cells Odisha, Balaghat (Madhya Pradesh), Nagpur–
Bhandara (Maharashtra)

Mica Electrical insulation, cosmetics, Koderma (Jharkhand), Nellore (Andhra
paints Pradesh), Rajasthan

Gypsum Plaster of Paris, false ceilings, Rajasthan, Tamil Nadu
cement

Salt (halite) Cooking and preserving food Sambhar Lake (Rajasthan); coastal salt pans of
Gujarat and Tamil Nadu

What the list will teach you: nearly every hard thing around you began as a rock or
a mineral dug out of the ground somewhere in India — and every one of them is
non-renewable. That is why the chapter asks us to conserve rocks and minerals and
use them responsibly.

Add one column of your own: “Can it be reused or recycled?” Iron, aluminium and
copper can be melted and used again — recycling them saves both the mineral and
the fuel needed to mine it.

Q4 You are an eco-club monitor. Organise a tree plantation drive in your school with
the help of your teacher. List the steps required for organising this activity. Prepare
a one-page report listing the names of the trees planted along with their
importance.

Part A — Steps for organising the drive

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Class 6 Science Chapter 11 Nature’s Treasures AglaSem · NCERT Solutions

1. Take permission and fix a date. Meet the Principal with a written proposal. Choose the
beginning of the monsoon — Van Mahotsav week in July is the best time, as new plants get
natural rain.
2. Survey the space. Walk around the school and mark on a rough map where trees can go —
along the boundary wall, behind the playground, near the gate. Avoid places above water
pipes or under electric wires.
3. Choose the right trees. Prefer native species suited to your area, and mix fruit, flower and
shade trees.
4. Arrange saplings and materials. Ask the Forest Department nursery, the municipality or a
local nursery — they often give saplings free. Collect spades, watering cans, manure, and
tree guards made of bamboo or old wire mesh.
5. Form teams. Two students per sapling, with one class teacher in charge of each group.
Assign jobs: digging, planting, watering, labelling, photography, reporting.
6. Dig the pits a day earlier — about 45 cm across and 45 cm deep — and mix in compost or
manure.
7. Plant on the day. Remove the polythene bag carefully without breaking the root ball, place
the sapling upright, fill and press the soil, water at once, and fix the tree guard and a name
label.
8. Plan the aftercare — the most important step. Make a watering roster for the whole year,
including the summer holidays. A sapling that nobody waters is a wasted sapling.
9. Record and celebrate. Photograph each sapling with its team, measure its height every
month, and hold a small “tree adoption” certificate ceremony.

Part B — Sample one-page report

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Class 6 Science Chapter 11 Nature’s Treasures
a g l AglaSem · NCERT Solutions

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Report: Tree Plantation Drive, Van Mahotsav Week

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Date: 12 July Place: School boundary and back garden Saplings planted: se
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30 Participants: 60 students of Classes 6–8, 5 teachers, 2 gardeners
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Neem 6 Medicinal leaves, twigs used as datun, keeps insects away, dense

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Banyan 1
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Huge shade, fruits feed birds and bats; our national tree

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Fruit rich in vitamin C — the same nellikai

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Jamun 3 Fruit for people and birds; roots take up a lot of water and hold the

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Moringa 4 Leaves and pods are highly nutritious; grows quickly
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Curry leaf and tulsi 4 Kitchen and medicinal use; suitable for pots near the classrooms

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gardener waters on holidays. Height of each sapling to be measured on the first of

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every month and entered in the eco-club register.
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What we learnt: planting takes one morning; keeping a tree alive takes a year.

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Increasing the green cover is not an event — it is a habit.

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Why native trees: a neem, peepal or jamun is already suited to the local soil and
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rainfall, needs little care once established, and feeds local birds and insects. An

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