SOF ISO Sample Paper 2026 Class 11

CLASS

11
SAMPLE PAPER
2025-26 SOF NATIONAL
SCIENCE OLYMPIAD

Total Questions : 50 Time : 1 hr.
PATTERN & MARKING SCHEME
Section (1) Physics & Chemistry (2) Achievers Section (3) Mathematics
or
Biology
No. of Questions 25 5 20
Marks per Ques. 1 3 1

SYLLABUS
Section – 1 : Physics : Units and Measurements, Mechanics, Properties of Matter, Heat and
Thermodynamics, Oscillations, Waves.
Chemistry : Some Basic Concepts of Chemistry, Structure of Atom, Classification of Elements
and Periodicity in Properties, Chemical Bonding and Molecular Structure, Thermodynamics,
Equilibrium, Redox Reactions, Organic Chemistry - Some Basic Principles and Techniques,
Hydrocarbons.
Section – 2 : Higher Order Thinking Questions - Syllabus as per Section – 1.
Section – 3 : Sets, Relations and Functions, Logarithms, Complex Numbers, Linear Inequalities,
Sequences and Series, Trigonometry, Straight Lines, Conic Sections, Permutations and
Combinations, Binomial Theorem, Statistics, Limits and Derivatives, Probability, Introduction to
3-D Geometry.
OR
Section – 3 : Diversity in the Living World, Structural Organisation in Plants and Animals,
Cell : Structure and Functions, Plant Physiology, Human Physiology.

PHYSICS AND CHEMISTRY
1. 28 g of iron is reacted with hydrochloric acid separately as given in the following two cases:
Case I : In a closed vessel of fixed volume.
Case II : In an open beaker at 27°C.
Then the work done in case I and case II are respectively
(Given, R = 2 cal K–1 mol–1)
(A) 0 and –600 cal (B) 0 and –300 cal
(C) –300 cal and 0 (D) –600 cal and 0
2. Arrange the following compounds in the increasing oxidation number of carbon
atom.
CH4 CH3Cl CO CO2 NaHCO3
P Q R S T

(A) P = Q < R < S < T (B) P = Q < S < R < T
(C) P < Q < R < S = T (D) R = Q < P < S < T

Sample Paper | Class-11 | 1

3. X + 2Y + 3Z  XY2 Z3
Reaction of 6.0 g of X, 6.0 × 1023 atoms of Y and 0.036 mol of Z yields 4.8 g of
compound XY2Z3. If the atomic masses of X and Z are 60 u and 80 u, respectively,
the atomic mass of Y is
(Given : Avogadro no. = 6 × 1023)
(A) 40 u (B) 50 u (C) 60 u (D) 70 u
4. A satellite is launched from international space station from point P, which is at a
distance of 4R from the centre of the Earth of radius R. The speed of the satellite
is v in a direction making 30° with the line joining the centre of the Earth and
point P, as shown in the given figure.
v

30°

P
4R

R

What will be the speed v if the satellite passes grazing the surface of the Earth?
(Consider only gravitational interaction.)
4000 8000
(A) m/s (B) m/s
2 2
6000
(C) m/s (D) 8000 2 m/s
2
5. Two students of equal mass stand at the opposite ends of the diameter of a
turntable disc of certain mass, moving with constant angular velocity. The two
students make their way towards the middle of the turntable at equal rates.
Which one of the following statements is correct?
(A) Kinetic energy of rotation has increased while angular momentum remains same.
(B) Kinetic energy of rotation has decreased while angular momentum remains
same.
(C) Kinetic energy of rotation has decreased but angular momentum has increased.
(D) Both kinetic energy of rotation and angular momentum have decreased.
6. A small pulse is travelling with a speed v in a string. At time t = 0, it is moving
towards the free end as shown in the given figure.
L/2
v
t=0
s << L
x=0 x=L
Fixed end L Free end
Which of the following pairs is/are incorrectly matched?

2 | Sample Paper | Class-11

L
(i) t= (p)
v
2L
(ii) t= (q)
v

3L
(iii) t = (r)
v
(A) (i) and (iii) only (B) (ii) only
(C) (iii) only (D) All pairs are correctly matched

ACHIEVERS SECTION
7. A solution contains 0.1 M Cl– and 0.001 M CrO42–, in this solution solid AgNO3 is
gradually added. Assume that the addition does not change in volume.
Given : Ksp (AgCl) = 1.7 × 10–10 M2 and
Ksp (Ag2CrO4) = 1.9 × 10–12 M3.
Select the incorrect statement(s) from the following.
I. AgCl will precipitate first as the amount of Ag+ needed to precipitate is low.
II. Ag2CrO4 will precipitate first because the amount of Ag+ needed is low.
III. Remaining concentration of Cl– when Ag2CrO4 will start precipitating will be
4.9 × 10–4 M.
(A) I, II and III (B) II only (C) I and III only (D) II and III only

8. Two identical blocks X and Y each of mass 2 kg are hanging stationary by a light
inextensible flexible string, passing over a light and frictionless pulley, as shown
in the given figure. A shell P of mass 1 kg moving vertically upward with velocity
9 m/s collides with block Y and is stuck to it.

X Y

P

Which of the following statements are correct?
(i) The time after which block Y starts moving downwards is 0.3 s.
(ii) The maximum height reached by Y is 0.45 m.
(iii) The loss of mechanical energy upto the instant till Y reaches highest point is 20 J.
(A) (i) and (ii) only (B) (ii) and (iii) only
(C) (i) and (iii) only (D) (i), (ii) and (iii)

Sample Paper | Class-11 | 3

MATHEMATICS

9. If X = {4n – 3n – 1 : n ∈ N} and Y = {9(n – 1) : n ∈ N}, then X ∪ Y is equal to
(A) X (B) Y (C) N (D) Z
10. If all the words (with or without meaning) having five letters, formed by using
the letters of the word SMALL and arranged as in a dictionary, then the position
of the word SMALL, is
(A) 46th (B) 59th (C) 52nd (D) 58th

BIOLOGY

9. Glucagon is a hormone that stimulates the conversion of glycogen into glucose
in response to low blood glucose concentration.
Which other hormone has a similar effect on blood glucose concentration?
(A) Anti-diuretic hormone (B) Adrenaline
(C) Insulin (D) Testosterone
10. Consider the following statements regarding the given figure and select the
incorrect one(s).

L M
N

O

(i) ‘L’ is the collenchymatous hypodermis that provides mechanical strength and
flexibility to the young dicot stems.
(ii) ‘M’ is the innermost layer of cortex which usually possesses casparian strips.
(iii) ‘N’ is the parenchymatous pericycle that synthesises food.
(iv) ‘O’ is xylem which is exarch with respect to the positions of protoxylem and
metaxylem.
(A) (i) only (B) (i) and (ii) only
(C) (iv) only (D) (ii), (iii) and (iv) only

ANSWER KEY
Physics and Chemistry 1. (B) 2. (C) 3. (B) 4. (B) 5. (A) 6. (B) 7. (D) 8. (A)
Mathematics 9. (B) 10.(D)
Biology 9. (B) 10.(D)

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