AHSEC HS 2nd Year Question Paper 2019 Chemistry

Total number of pages—16

29T CHEM

2019

CHEMISTRY
(Theory)

Full Marks : 70
Pass Marks : 21

Time : Three hours

The figures in the margin indicate full marks
for the questions.

General Instructions :
(i) All questions are compulsory.
(ii) Marks for each question are indicated against it.
(iii) Answers should be specific and to the point.
(iv) Question numbers 1 to 8 consist of eight very short
answer type questions and carry 1 mark each. 1×8 = 8
(v) Question numbers 9 to 18 consist of ten short answer
type questions and carry 2 marks each. 2×10 = 20
(vi) Question numbers 19 to 27 consist of nine short answer
type questions and carry 3 marks each. 3×9 = 27
(vii) Question numbers 28 to 30 consist of three long answer
type questions and carry 5 marks each. 5×3 = 15

Total = 70

Contd.

1. Which of the following lattices has the highest packing efficiency ? 1

Ó¬˘Ó¬ ά◊À~‡ fl¬1± Œfl¬±ÚÀȬ± Œ˘øȬÂ√1 Œ¬Ûøfl¬— é¬Ó¬± ’±È¬±˝◊Ó¬Õfl¬ Œ¬ıøÂ√ ∑
(a) simple cubic closed packed (ccp) lattice

¸1˘ ‚Úfl¬œ˚˛ øÚ1g™ (ccp) Œ˘øȬÂ√
(b) body-centered cubic (bcc) lattice

˙1œ1 Œfl¬fœÓ¬ ‚Úfl¬œ˚˛ (bcc) Œ˘øȬÂ√
(c) hexagonal closed packed (hcp) lattice

¯∏άˇˆ≈¬Êœ˚˛ øÚ1g™ ¸—fl≈¬ø˘Ó¬ (hcp) Œ˘øȬÂ√
2. Define molality of a solution. 1

¤È¬± ^ª1 ˜À˘ø˘øȬ1 ¸—:± ø˚˛±º
3. For a zero order reaction will the molecularity be equal to zero ? Explain.
1
˙”Ú… Sê˜1 ø¬ıøSê˚˛± ¤È¬±1 ’±Ìøªfl¬Ó¬± (molecularity) ˙”Ú… ˝¬ı ¬¬Û±À1ÀÚ ∑ ¬ı…±‡…± fl¬1±º
4. In the first transition series of elements, which element shows highest
oxidation state ? 1
√õ∂Ô˜ ¸—Sê˜Ì˙œ˘ Œ|Ìœ1 Œ˜Ã˘À¬ı±11 øˆ¬Ó¬1Ó¬ Œfl¬±ÚÀȬ± Œ˜Ã˘˝◊ ¸À¬ı«±2‰¬ ʱ1Ì ’ª¶ö± Œ‡≈ª±˚˛ ∑
5. Write the IUPAC names of [Co(NH3)4Cl(NO2)]Cl and K2 [NiCl4]. 1
[Co(NH3)4Cl(NO2)]Cl ’±1n∏ K2 [NiCl4] Œ˚÷≈Ȭ±1 IUPAC Ú±˜ ø˘‡±º

6. Give one example of globular protein. 1
¬ıÓ«¬≈˘±fl¬±1 √õ∂øȬÚ1 ¤È¬± ά◊±˝1Ì ø˚˛±º
7. The curve showing the variation of adsorption with pressure at constant
temperature is called . (Fill in the blank) 1
ø¶ö1 ά◊¯ûÓ¬±Ó¬ ‰¬±¬Û1 ˘·Ó¬ ’øÒÀ˙±¯∏Ì1 ¬Ûø1¬ıÓ«¬Ú Œ‡≈›ª± ˜±Úfl¬ Œ¬ı±˘± ˝˚˛º
[‡±˘œ ͬ±˝◊ ¬Û≈1Ì fl¬1±]
29T CHEM [2]

8. What are the monomers of Buna-S rubber ? 1

¬ı≈Ú±-S 1±¬ı±11 ˜Ú혱1¸˜”˝ øfl¬ øfl¬ ∑

9. What is meant by positive deviations from Raoult’s law ? How is the sign of
 mix H related to positive deviations from Raoult’s law ? 1+½+½=2

1±Î¬◊åȬ1 ¸”S1 ÒÚ±Rfl¬ ø¬ı‰≈¬…øÓ¬ ‚Ȭ± ¬ı≈ø˘À˘ øfl¬ ¬ı≈ʱ ˚±˚˛∑ 1±Î¬◊åI◊1 ¸”S1 ÒÚ±Rfl¡ ø¬ı‰≈¬…øÓ¬1 Δ¸ÀÓ¬
 H ø‰¬˝êÀȬ±1 ¸•Ûfl«¡ øfl¡∑
mix

10. Calculate the mass of compound (molar mass = 256 g mol –1 ) to be dissolved
in 75 g of benzene to lower its freezing point by 0.48 K (Kf = 5.12 K kg mol–1 ).
2

75 g Œ¬ıÚøÊÚ1 ˘·Ó¬ Œfl¬±ÀÚ± ¤È¬± Œ˚÷ [’±Ìøªfl¬ ˆ¬1‘ 256 g mol –1 ] ^¬ıœˆ”¬Ó¬ fl¬ø1À˘ Œ¬ıÚøÊÚ1
ø˝˜±—fl¬ 0.48 K fl¬ø˜ ˚±˚˛ (Kf = 5.12 K kg mol–1 ) º Œ˚÷ÀȬ±1 ˆ¬1 øÚÌ«˚˛ fl¬1±º

1.0 g of a nonelectrolyte solute dissolved in 50g of benzene lowered the
freezing point of benzene by 0.40 K. The freezing point depression constant
of benzene is 5.12 K kg mol–1. Find the molar mass of the solute.

1.0 g ø¬ı≈…» ’ø¬ıÀù≠¯∏… ^±¬ı… ¤È¬± 50g Œ¬ıÚƒøÊÚÓ¬ ^ªœˆ”¬Ó¬ fl¬ø1À˘ Œ¬ıÚƒøÊÚ1 ø˝˜±—fl¬ ’ªÚ˜Ú ˝˚˛
0.40 K. Œ¬ıÚƒøÊÚ1 ø˝˜±—fl¬ ’ªÚ˜Ú ÒËn ªfl¬ Δ˝ÀÂ√ 5.12 K kg mol–1º ^±¬ı…ÀȬ±1 ˜í˘±1 ˆ¬1 øÚÌ«˚˛
fl¬1±º

11. State Faraday’s first law. How much charge in terms of Faraday is required
for the reduction of 1 mole of Cu 2+ to Cu ? 1+1=2

Ù¬±1±Àά1 √õ∂Ô˜ ¸”SÀȬ± ø˘‡±º 1 mole Cu2+ fl¬ Cu Δ˘ ø¬ıʱø1Ó¬ fl¬ø1¬ıÕ˘ øfl¬˜±Ú ¬Ù¬±1±Àά ’±Ò±Ú
(charge) ˘±ø·¬ı ∑

29T CHEM [3] Contd.

Define conductivity of an electrolytic solution. How does it vary with decrease
in concentration and why ?
¤È¬± ø¬ı≈…»ø¬ıÀù≠¯∏… ^ª1 ¬Ûø1¬ı±ø˝Ó¬±1 ¸—:± ø˚˛±º ·±Ï¬ˇÓ¬± fl¬˜±1 ˘À· ˘À· ˝◊ Œfl¬ÀÚÀ1 ’±1n∏ øfl¬˚˛
¬Ûø1¬ıøÓ¬«Ó¬ ˝˚˛ ∑

12. Calculate e.m.f. of the following cell at 298 K : 2
Ó¬˘Ó¬ ø˚˛± Œfl¬±¯∏ÀȬ±1 e.m.f. 1 ˜±Ú 298 K Ó¬ øÚÌ«˚˛ fl¬1± .
2 3
2Cr  s   3Fe  0.1 M   2Cr 0.01M   3Fe s 

Given : [ø˚˛± ’±ÀÂ√]
E  3
Cr Cr    0.74V &
E  2
Fe Fe    0.44V
What type of a battery is the lead storage battery? Write the anode and the
cathode reactions and the overall reaction occurring in a lead storage battery.
½+1½=2

Œ˘Î¬ ©ÜíÀ1Ê Œ¬ıȬ±1œ øfl¬ √õ∂fl¬±11 Œ¬ıȬ±1œ ∑ Œ˘Î¬ ©ÜíÀ1Ê Œ¬ıȬ±1œÓ¬ ¸—‚øȬӬ Œ˝±ª± ¤Úíά ’±1n∏
Œfl¬Ôíά1 ø¬ıøSê˚˛± ’±1n∏ ¸•Û”Ì« ø¬ıøSê˚˛±ÀȬ± ø˘‡±º

13. For a reaction A  B  P , the rate is given by — 1½+½=2
Rate = [A][B]2
(i) How is the rate of reaction affected if the concentration of B is doubled ?
(ii) What is the overall order of reaction if A is present in large excess ?

A  B  P , ø¬ıøSê˚˛±ÀȬ±1 fl¬±1ÀÌ ø˚˛± ’±ÀÂ√ ,

˝±1 = [A][B]2
(i) ˚ø B 1 ·±Ï¬ˇÓ¬± ≈&Ì ˝˚˛, ŒÓ¬øÓ¬˚˛± ø¬ıøSê˚˛±ÀȬ±1 ˝±1 Œfl¬ÀÚÕfl¬ ¬Ûø1ªÓ«¬Ú ˝¬ı ∑
(ii) ˚ø A1 ά◊¬Ûø¶öøÓ¬ ¬ıUÓ¬ Œ¬ıøÂ√ ˝˚˛ ŒÓ¬ÀôL√ ø¬ıøSê˚˛±ÀȬ±1 ˜≈ͬ Sê˜ øfl¬˜±Ú ˝¬ı ∑
29T CHEM [4]

Pt
For a reaction : 2NH3 (g)  N2 (g) + 3H2 (g) 1+1=2
Rate = k ;
(i) Write the order and molecularity of this reaction.
(ii) Write the unit of k.

Pt
¤˝◊ ø¬ıøSê˚˛±ÀȬ±1 fl¬±1ÀÌ . 2NH3 (g)  N2 (g) + 3H2 (g)

˝±1 = k ;
(i) ø¬ıøSê˚˛±ÀȬ±1 Sê˜ ’±1n∏ ’±Ìøªfl¬Ó¬± ø˘‡±º
(ii) k-1 ¤fl¬fl¬ ø˘‡±º

14. What are alloys ? Name the metals used for the formation of bronze.
1+1=2
¸—fl¬1 Ò±Ó≈¬ øfl¬ ∑ ¬ıË?1 ·Í¬ÚÓ¬ ¬ı…ª˝+Ó¬ Ò±Ó≈¬Àfl¬˝◊Ȭ±1 Ú±˜ ø˘‡±º

2  salts are coloured. Give reason.
15. Zn 2  salts are colourless while Cu
2
2
Zn 2  ˘¬ı̸˜”˝ ¬ı1Ì˝œÚ ’±Ú˝±ÀÓ¬ Cu ˘¬ı̸˜”˝ 1„œÚº fl¬±1Ì À˙«±ª±º

Calculate the number of unpaired electrons in Cr 3+ and V 3+ ions.
3+
Cr ’±1n∏ V 3+ ’±˚˛ÚÓ¬ Ôfl¬± ’˚≈¢¨ ˝◊À˘"™√Ú1 ¸—‡…± ·ÌÚ± fl¬1±º

16. How will you convert the following (any two) ? Give chemical equations
only. 1+1=2

Ó¬˘Ó¬ ø˚˛±À¬ı±1 Œfl¬ÀÚÀ1 ¬Ûø1ªÓ«¬Ú fl¬ø1¬ı± [ø˚Àfl¬±ÀÚ± ≈Ȭ±] ∑ Œfl¬ª˘ 1±¸±˚˛øÚfl¬ ¸˜œfl¬1Ì ø˚˛±º
(i) Ethane to bromoethene
˝◊ÀÔÚ1 ¬Û1± ¬ıËí˜í ˝◊øÔÚÕ˘

29T CHEM [5] Contd.

(ii) Benzene to biphenyl
Œ¬ıÚøÊÚ1 ¬Û1± ¬ı±˝◊øÙ¬Ú±˝◊˘Õ˘

(iii) Aniline to chlorobenzene
¤øÚø˘Ú1 ¬Û1± ¬flv¬í1íÀ¬ıÚøÊÚÕ˘

17. Give reasons : 2
fl¬±1Ì À˙«±ª± .

(a) n-Butyl bromide has higher boiling point than t-Butyl bromide.

n-ø¬ıά◊Ȭ±˝◊˘ ¬ıË혱˝◊ά1 ά◊Ó¬˘±—fl¬ t-ø¬ıά◊Ȭ±˝◊˘ ¬ıË혱˝◊ά1 ά◊Ó¬˘±—fl¬Ó¬Õfl¬ Œ¬ıøÂ√º

(b) Racemic mixture is optically inactive.

Œ1ø‰¬˜œ˚˛ ø˜| ’±À˘±fl¬œ˚˛ˆ¬±À¬ı øÚø©ç¬˚˛º

What are ambident nucleophiles ? Give two examples of it.

¤ø•§ÀάKȬ øÚά◊øflv¬’íÙ¬±˝◊˘ øfl¬ ∑ ˝◊˚˛±1 ≈Ȭ± ά◊±˝1Ì ø˚˛±º

18. Answer the following questions : (any one)
Ó¬˘1 √õ∂ùüÀfl¬˝◊Ȭ±1 ά◊M1 ø˚˛± . [ø˚Àfl¡±ÀÚ± ¤È¬±]
(i) Give reason for the higher boiling point of ethanol in comparison to
methoxymethane. 2
˝◊Ô±Ú˘1 ά◊Ó¬˘±—fl¬ ø˜Ôø'ø˜ÀÔÚ1 Ó≈¬˘Ú±Ó¬ øfl¬˚˛ Œ¬ıøÂ√ fl¬±1Ì À˙«±ª±º
(ii) Aniline does not undergo Friedel-Crafts reaction. Why ? 2
¤øÚø˘ÀÚ øÙˬÀά˘-Sê±Ùƒƒ¬È¬ ø¬ıøSê˚˛± ‚Ȭ±¬ı ŒÚ±ª±À1º øfl¡˚˛∑

29T CHEM [6]

19. (a) A compound forms hexagonal close packed (hcp) structure. What is
the total number of voids in 0.5 mol of it ? How many of these are
tetrahedral voids ? 2
¤È¬± Œ˚÷˝◊ ¯∏άˇˆ≈¬Êœ˚˛ øÚ1g™ ¸—fl≈¬ø˘Ó¬ (hcp) ·Í¬Ú1 ¸‘ø©Ü fl¬À1º ¤˝◊ Œ˚÷ÀȬ±1 0.5 mol Ó¬
˜≈ͬÀÓ¬ øfl¬˜±ÚȬ± 1g™ ’±ÀÂ√ ∑ ˝◊˚˛±À1 øfl¬˜±ÚȬ± ‰¬Ó≈¬Ù«¬˘fl¬œ˚˛ 1g™ ∑
(b) What is the formula of a compound in which the element Y forms cubic
closed packed (ccp) lattice and atoms of X occupy l/3rd of tetrahedral
voids ? 1
Œfl¬±ÀÚ± ¤È¬± Œ˚÷Ӭ Y ’Ì≈Àª ‚Úfl¬œ˚˛ øÚ1g™ ¸—fl≈¬ø˘Ó¬ (ccp) ·Í¬Ú1 ¸‘ø©Ü fl¬À1 ’±1n∏ X
’Ì≈Àª ‰¬Ó≈¬Ù«¬˘fl¬œ˚˛ 1g™1 ¤fl¬ Ó‘¬Ó¬œ˚˛±—˙ [l/3] ’øÒfl¬±1 fl¬À1º Œ˚÷ÀȬ±1 ¸—Àfl¬Ó¬ øÚÌ«˚˛
fl¬1±º

Calculate the packing efficiency of a simple cubic lattice. 3
¤È¬± ¸1˘ ‚Ú±fl‘¬øÓ¬ Œ˘øȬÂ√ 1 ¬Û≈?œfl¬1Ì é¬Ó¬± ·ÌÚ± fl¬1±º

20. (a) What will be the effect of temperature on rate constant ? 1
ø¬ıøSê˚˛±1 ·øÓ¬ ÒËn ªfl¬1 ›¬Û1Ó¬ ά◊¯ûÓ¬±1 √õ∂ˆ¬±ª Œfl¬ÀÚ ˝√√¬ı∑
(b) A first order reaction has a rate constant of 102 s 1 . How much time
will be taken for 20g of the reactant to be reduced to 5g ?
2
¤È¬± √õ∂Ô˜ Sê˜1 ø¬ıøSê˚˛±1 ·øÓ¬ ÒËn∏ªfl¡1 ˜±Ú 102 s1 º ¤˝◊√ ø¬ıøSê˚˛±Ó¬ ø¬ıøSê˚˛±Ê±Ó¬ ¬Û±Ô«
20g 1 ¬Û1± 5g Δ˘ ˝}√±¸ ˝√√¬ıÕ˘ øfl¡˜±Ú ¸˜˚˛ ˘±ø·¬ı∑

21. What are the differences between physisorption and chemisorption ? Give
reason why a finely divided substance is more effective as an adsorbent.
2+1=3
Œˆ¬ÃøÓ¬fl¬ ’øÒÀ˙±¯∏Ì ’±1n∏ 1±¸±˚˛øÚfl¬ ’øÒÀ˙±¯∏Ì1 √¬Û±Ô«fl¬… øfl¬ øfl¬ ∑ Œ¬ıøÂ√Õfl¬ &øάˇ fl¬1±¬ ¬Û±Ô« øfl¬˚˛
’øÒÀ˙±ø¯∏Ó¬ ¬Û±Ô« ø˝‰¬±À¬Û Œ¬ıøÂ√ fl¬±˚«fl¬1œ ∑

29T CHEM [7] Contd.

What is an adsorption isotherm ? In reference to Freundlich adsorption
isotherm write the expression for absorption of gases on solids in the form
of an equation. 1+2=3

’øÒÀ˙±¯∏Ì ’±˝◊Â√íÔ±˜« fl¬±fl¬ Œ¬ı±À˘ ∑ ŒÙˬGø˘fl¬ ’øÒÀ˙±¯∏Ì ’±˝◊Â√íÔ±˜«1 ¸˝±˚˛ Δ˘ Œ·Â√1 ’øÒÀ˙±¯∏Ì1
’øˆ¬¬ı…øMêÀȬ± ¸˜œfl¬1Ì ø˝‰¬±À¬Û ø˘‡±º

22. Explain role of the following in the processes mentioned :
1½+1½=3

(i) Depressant in froth floatation process

(ii) Limestone in the metallurgy of iron.

ά◊À~‡ fl¬1± ¬ÛXøÓ¬À¬ı±1Ó¬ Ó¬˘Ó¬ ø˚˛± ^ª…À¬ı±11 ˆ”¬ø˜fl¬± ¬ı…±‡…± fl¬1± .

(i) ŒÙ¬Ú ›¬Û„Ú ¬ÛXøÓ¬Ó¬ øÚ•ßfl¬±1œ ^ª…

(ii) ’±˝◊ 1Ú1 Ò±Ó≈¬ø¬ı…±Ó¬ ‰”¬Ìø˙˘º

Write short notes on : 1½+1½=3

(i) Zone refining

(ii) Froth floatation process

‰¬˜≈ ŒÈ¬±fl¡± ø˘‡± –

(i) Ê√í Ú ø1Ù¬±˝◊√øÚ—

(ii) ŒÙ¬Ú ›¬Û„√√Ú ¬ÛXøÓ¬

29T CHEM [8]

23. Answer the following :

Ó¬˘Ó¬ ø˚˛±À¬ı±11 ά◊M1 ø˚˛± .

(a) Noble gases have very low boiling points. Why ? 1

¸z±ôL√ Œ·Â√¸˜”˝ 1 ά◊Ó¬˘±—fl¬ ’Ó¬…ôL√ fl¬˜º øfl¬˚˛ ∑

(b) Copper does not dissolve in HCl while it does dissolve in HNO3.
Explain. 2

fl¬í¬Û±1 HCl Ó¬ ^ªœˆ”¬Ó¬ Ú˝˚˛ øfl¬c HNO3 Ó¬ ^ªœˆ”¬Ó¬ ˝˚˛º ¬ı…±‡…± fl¬1±º

24. Explain the following with an example : 1½+1½=3

ά◊±˝1̸˝ Ó¬˘Ó¬ ø˚˛±À¬ı±1 ¬ı…±‡…± fl¬1± .

(i) Kolbe’s reaction.
fl¬í{§1 ø¬ıøSê˚˛±º

(ii) Reimer-Tiemann reaction.

Œ1˝◊˜±1-øȬÀ˜Ú ø¬ıøSê˚˛±º

(i) A Grignard reagent reacts with methanal to form

CH 3  CH  CH 2  OH
|
CH 3

Identify the Grignard reagent. 1

¤È¬± ø¢∂·Ú±Î«¬1 ø¬ıfl¬±1Àfl¬ ø˜Ô±ÀÚ˘1 ˘·Ó¬ ø¬ıøSê˚˛± fl¬ø1 CH 3  C| H  CH 2  OH
CH 3
ά◊»¬Ûiß fl¬À1º ø¢∂·Ú±Î«¬1 ø¬ıfl¬±1fl¬ÀȬ± ø‰¬Ú±Mê fl¬1±º

29T CHEM [9] Contd.

(ii) Name the reaction : 1

ø¬ıøSê˚˛±ÀȬ±1 Ú±˜ ø˘‡± .
OH OH
CHO
CHCI3 + aq. NaOH

H

(iii) Write IUPAC names of the following ether. 1

Ó¬˘Ó¬ ø√˚˛± ˝◊√Ô±11 IUPAC Ú±˜ÀȬ± ø˘‡±º
H3 C CH3

OC2H5

25. What happens when — 1+1+1=3

øfl¬ ‚ÀȬ, Œ˚øÓ¬˚˛± —
(i) Cyclohexanecarbaldehyde reacts with PhMgBr and then H3O+.
‰¬±˝◊flv¬íÀ˝À'Úfl¬±À¬ı«˘øά˝±˝◊1 Δ¸ÀÓ¬ PhMgBr ’±1n∏ H3O+ Œ˚˛ ø¬ıøSê˚˛± fl¬À1º
(ii) Carbonyl compound is treated with zinc - amalgam and concentrated
hydrochloric acid.
fl¬±¬ı«øÚ˘ Œ˚÷fl¬ øÊ—fl¬ ¤˜±˘·±˜ ’±1n∏ ·±Ï¬ˇ ˝±˝◊Eíflv¬ø1fl¬ ¤øÂ√ά1 ¬Z±1± ø¬ıøSê˚˛± ‚Ȭ±À˘ øfl¬
˝¬ı ∑
(iii) Write the major and minor product of ‘Bromination of anisole in
ethanoic acid medium’.
˝◊√Ô±Úø˚˛fl¡ ¤ø‰¬Î¬ ˜±Ò…˜Ó¬ ¤øÚÂ√˘1 ¬ıËí ø˜ÀÚÂ√Ú ø¬ıøSê˚˛±Ó¬ ά◊»¬Ûiß Œ˝√√±ª± ˜≈‡… ’±1n∏ Œ·ÃÌ
ø¬ıøSê˚˛±Ê√±Ó¬ ¬Û√±Ô« Œfl¡˝◊√Ȭ± ø˘‡±º

29T CHEM [ 10 ]

An organic compound with the molecular formula C9H10O forms 2, 4-DNP
derivative, reduces Tollens’ reagent and undergoes Cannizzaro reaction. On
vigorous oxidation, it gives 1, 2-benzenedicarboxylic acid. Identify the
compound. 3

C9H10O ’±Ìøªfl¬ ¸”S1 ¤È¬± Δʪ ’Ì≈Àª 2, 4-DNP ŒÎ¬ø1Àˆ¬øȬˆƒ¬ ·Í¬Ú fl¬À1, ø˚ ȬÀ˘k1
ø1¤ÀÊ∞I◊fl¬ ø¬ıʱø1Ó¬ fl¬À1 ’±1n∏ Œfl¬øÚ7¬¬¬±1í ø¬ıøSê˚˛± Œ‡≈ª±˚˛º Ó¬œ¬ıˈ¬±À¬ı ʱø1Ó¬ fl¬1±1 ¬Û±Â√Ó¬ ˝◊
1, 2-Œ¬ıÚøÊÚά±˝◊fl¬±¬ı«ø'ø˘fl¬ ’•° øÀ˚˛º Œ˚÷ÀȬ± øÚÌ«˚˛ fl¬1±º

26. Identify the product of the following reactions : (any two) 1½+1½=3

Ó¬˘Ó¬ ø˚˛± ø¬ıøSê˚˛±À¬ı±11 ø¬ıøSê˚˛±Ê±Ó¬ ¬Û±Ô«À¬ı±1 ø‰¬Ú±Mê fl¬1± . [ø˚Àfl¡±ÀÚ± ≈√Ȭ±]

( i ) H N  NH 2
(a) CH 3  C  O   2     ?
|
( ii ) KOH / Glycol , 
CH 3

NaOH I 2
(b) C 2 H 5  CO  CH 3      ?

O
||  conc. KOH  ?
(c) 2
C
CH 3 H

27. Give one chemical test to distinguish between the following pairs of
compounds : 1½+1½=3

(i) Methylamine and dimethylamine

(ii) Aniline and benzylamine

29T CHEM [ 11 ] Contd.

Ó¬˘Ó¬ ø˚˛± Œ˚÷1 Œ˚±1ø¬ı˘±fl¬1 √¬Û±Ô«fl¬… Œ‡≈ª±¬ıÕ˘ ¤È¬± 1±¸±˚˛øÚfl¬ ø¬ıøSê˚˛± ø˘‡± .
(i) ø˜Ô±˝◊˘¤˜±˝◊Ú ’±1n∏ ά±˝◊ø˜Ô±˝◊˘¤˜±˝◊Ú
(ii) ¤øÚø˘Ú ’±1n∏ Œ¬ıÚʱ˝◊˘¤˜±˝◊Ú

Account for the following :

(i) Ethylamine is soluble in water whereas aniline is not.

(ii) Methylamine in water reacts with ferric chloride to precipitate hydrated
ferric oxide.

Ó¬˘Ó¬ ø˚˛±À¬ı±11 ¬ı…±‡…± ’±·¬ıÀϬˇ±ª± .
(i) ˝◊Ô±˝◊˘¤˜±˝◊Ú ¬Û±ÚœÓ¬ ^ªœˆ”¬Ó¬ ˝˚˛ øfl¬c ¤øÚø˘Ú Ú˝˚˛º
(ii) ¬Û±ÚœÓ¬ ø˜Ô±˝◊˘¤˜±˝◊ÀÚ ŒÙ¬ø1fl¬flv¬í1±˝◊ά1 Δ¸ÀÓ¬ ø¬ıøSê˚˛± fl¬ø1 Ê˘˚≈Mê ŒÙ¬ø1fl¬ ’í'±˝◊ά1
’Ò–Àé¬¬Û Œ¬Û˘±˚˛º

28. Answer the following questions :

Ó¬˘Ó¬ ø˚˛±À¬ı±11 ά◊M1 ø˚˛± .
(a) In which classes, the polymers are classified on the basis of molecular
forces ? 2

’±Ìøªfl¬ ¬ı˘1 ’±Ò±1Ó¬ Œ|Ìœø¬ıˆ¬±ÊÚ fl¬1± ¬ıUÀ˚±·œÀ¬ı±1 Œfl¬±ÚÀfl¡˝◊√Ȭ± Œ|̜Ӭ ¬ÛÀ1 ∑

(b) Sleeping pills are recommended to patient suffering from sleeplessness
but it is not advisable to take them without consulting the doctor. Justify.
1

ά±Mê√À1 øÚ^±˝œÚÓ¬±Ó¬ ˆ≈¬ø· Ôfl¬± Œ1±·œfl¬ ŒÈ¬±¬ÛøÚ ’Ú± ¬ıøάˇ ¢∂˝Ì1 ¬Û1±˜˙« øÀ˚˛, øfl¬c
ά±Mê11 ¬Û1±˜˙« ’ø¬ı˝ÀÚ ˝◊˚˛±fl¬ ¢∂˝ Ì fl¬1± ά◊ø‰¬Ó¬ Ú˝˚˛º ˚≈øMê ø˚˛±º

29T CHEM [ 12 ]

(c) What are tranquilizers ? Give an example. 1

Œ¬∏C—fl≈¬˝◊˘±˝◊ʱ1 ¬ı± ¸≈5fl¬±1œ øfl¬ ∑ ¤È¬± ά◊±˝1Ì ø˚˛±º

(d) Name one chemical responsible for the antiseptic property of Dettol.
1

ŒÎ¬È¬˘1 ¬ıœÊ±Ì≈¬ı±1fl¬ Ò˜« Œ‡≈›ª± 1±¸±˚˛øÚfl¬ ^¬ı… ¤È¬±1 Ú±˜ ø˘‡±º

29. Answer the following :

Ó¬˘1 √õ∂ùüÀ¬ı±11 ά◊M1 fl¬1± .
(a) What happens when sulphur dioxide gas is passed through
acidified potassium permanganate solution ? Write equation. 1

¤øÂ√ά ø˜ø|Ó¬ ¬ÛȬ±øÂ√˚˛±˜ ¬Û±1˜±—À·ÀÚȬ ^ª1 ˜±ÀÊø Â√±˘Ù¬±1 ά±˝◊ ’'±˝◊ά Œ·Â√ ¬Ûøͬ˚˛±À˘
øfl¬ ˝¬ı ∑ ø¬ıøSê˚˛±ÀȬ± ø˘‡±º

(b) Draw the structure of the following molecule and mention its shape :
2
XeF4

Ó¬˘Ó¬ ø˚˛± ’Ì≈ÀȬ±1 ·Í¬Ú-¸—Àfl¬Ó¬ ’“±øfl¬ Ó¬±1 ’±fl‘¬øÓ¬¬ ά◊À~‡ fl¬1± –
XeF4

(c) Complete the following reactions : (any two) 2

Ó¬˘1 ø¬ıøSê˚˛±À¬ı±1 ¸•Û”Ì« fl¬1± . [ø˚Àfl¬±ÀÚ± ≈Ȭ±]
(i) PCl3 + H2O 
 ?

(ii) XeF6 + H2O 
 ?

(iii) P4 + SO2Cl2 
 ?

29T CHEM [ 13 ] Contd.

(a) H2S acts only as reducing agent while SO2 acts as an oxidizing as well
as reducing agent. Why ? 2

H2S Œ˚˛ Œfl¬ª˘ ø¬ıʱ1fl¬ ø˝‰¬±À¬Û øSê˚˛± fl¬À1 ’±Ú˝±ÀÓ¬ SO2 Œ˚˛ ʱ1fl¬ ’±1n∏ ø¬ıʱ1fl¬
ά◊ˆ¬˚˛ˆ¬±Àª øSê˚˛± fl¬À1, øfl¬˚˛ ∑

(b) Describe the manufacture of ammonia by Haber’s process with
favourable conditions. 3

Œ˝¬ı±11 ¬ÛXøÓ¬À1 ¤˜íøÚ˚˛±1 ά◊»¬Û±Ú ’Ú≈fl”¬˘ ‰¬Ó«¬¸˜”˝ 1 Δ¸ÀÓ¬ ¬ı…±‡…± fl¬1±º

30. Answer the following questions :

Ó¬˘1 √õ∂ùüÀ¬ı±11 ά◊M 1 fl¬1± .

(a) Specify the oxidation numbers of the metals in the following
coordination entities : ½×4=2

Ó¬˘Ó¬ ø˚˛± ¸˜i§˚˛œ Œ˚÷1 Ò±Ó≈¬ø¬ı˘±fl¬1 ʱ1Ì ¸—‡…± øÚÌ«˚˛ fl¬1± .

(i) Co H 2O CN  en2  2

(ii)  CoBr2  en2 

(iii) PtCl 4  2 

(iv) K 3 Fe CN 6 

29T CHEM [ 14 ]

(b) What are carbohydrates ? Give the general formula of carbohydrates.
Why polysaccharides are called non-sugars ? 3

fl¬±¬ı«í˝±˝◊ÀEȬÀ¬ı±1 øfl¬ ∑ fl¬±í¬ı«˝±˝◊ÀEȬÀ¬ı±11 ¸±Ò±1Ì ¸—Àfl¬Ó¬ ø˘‡±º ¬Ûø˘À‰¬fl¬±1±˝◊άÀ¬ı±1fl¬
øfl¬˚˛ ’Ú±-˙fl«¬1± Œ¬ı±˘± ˝˚˛ ∑

———— ×————

29T CHEM [ 15 ]

29T CHEM [ 16 ] 45+