ICSE Chemistry Sample Paper - 2023 | ICSE Class 12 Science Sample Papers PDF Download

 Page 1


------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
1 
CHEMISTRY PAPER  1 
(THEORY) 
------------------------------------------------------------------------------------------------ 
Maximum Marks: 70 
Time Allowed: Three hours 
(Candidates are allowed additional 15 minutes for only reading the paper. 
They must NOT start writing during this time). 
---------------------------------------------------------------------------------------------------------------- 
This paper is divided into four sections – A, B, C and D. 
Answer all questions. 
Section A consists of one question having sub-parts of one mark each. 
Section B consists of ten questions of two marks each. 
Section C consists of seven questions of three marks each, and 
Section D consists of three questions of five marks each. 
Internal choices have been provided in one question each in Section B, 
Section C and Section D. 
All working, including rough work, should be done on the same sheet as, and 
adjacent to the rest of the answer. 
The intended marks for questions or parts of questions are given in brackets [ ]. 
Balanced equations must be given wherever possible and diagrams where they 
are helpful. 
When solving numerical problems, all essential working must be shown. 
In working out problems, use the following data: 
Gas constant R = 1 ?987 cal deg
-1
 mol
-1
 = 8 ?314 JK
-1
 mol
-1
  
= 0 ?0821 dm
3
 atm K
-1
mol
-1
 
1 l  atm = 1 dm
3
 atm  = 101 ?3 J.  1 Faraday = 96500 coulombs.   
Avogadro’s number = 6 ?023 ?10
23
. 
---------------------------------------------------------------------------------------------------------------- 
SECTION A – 14 MARKS 
Question 1  
(A) Fill in the blanks by choosing the appropriate word(s) from those given in the 
brackets: 
[two, Williamson’s synthesis, three, anisole, toluene, Friedel-Crafts alkylation, 
iodoform, sec
-1
, mol
-1
L sec
-1
, Lewis base, acetone, Lewis acid, chloroform, 
formaldehyde] 
[4×1] 
Page 2


------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
1 
CHEMISTRY PAPER  1 
(THEORY) 
------------------------------------------------------------------------------------------------ 
Maximum Marks: 70 
Time Allowed: Three hours 
(Candidates are allowed additional 15 minutes for only reading the paper. 
They must NOT start writing during this time). 
---------------------------------------------------------------------------------------------------------------- 
This paper is divided into four sections – A, B, C and D. 
Answer all questions. 
Section A consists of one question having sub-parts of one mark each. 
Section B consists of ten questions of two marks each. 
Section C consists of seven questions of three marks each, and 
Section D consists of three questions of five marks each. 
Internal choices have been provided in one question each in Section B, 
Section C and Section D. 
All working, including rough work, should be done on the same sheet as, and 
adjacent to the rest of the answer. 
The intended marks for questions or parts of questions are given in brackets [ ]. 
Balanced equations must be given wherever possible and diagrams where they 
are helpful. 
When solving numerical problems, all essential working must be shown. 
In working out problems, use the following data: 
Gas constant R = 1 ?987 cal deg
-1
 mol
-1
 = 8 ?314 JK
-1
 mol
-1
  
= 0 ?0821 dm
3
 atm K
-1
mol
-1
 
1 l  atm = 1 dm
3
 atm  = 101 ?3 J.  1 Faraday = 96500 coulombs.   
Avogadro’s number = 6 ?023 ?10
23
. 
---------------------------------------------------------------------------------------------------------------- 
SECTION A – 14 MARKS 
Question 1  
(A) Fill in the blanks by choosing the appropriate word(s) from those given in the 
brackets: 
[two, Williamson’s synthesis, three, anisole, toluene, Friedel-Crafts alkylation, 
iodoform, sec
-1
, mol
-1
L sec
-1
, Lewis base, acetone, Lewis acid, chloroform, 
formaldehyde] 
[4×1] 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
2 
 (i) Sodium phenoxide reacts with methyl chloride to give _______. The 
reaction is known as ________. 
 
 (ii) When the concentration of a reactant of first order reaction is tripled, the 
rate of reaction becomes ________ times. The unit of rate constant (k) for 
the first order reaction is ________. 
 
 (iii) In coordination complexes, the central metal atom or ion behaves as 
________ and the ligands behave as ________. 
 
 (iv) Calcium acetate on dry distillation gives ________ which gives _______ 
on heating with iodine and alkali. 
 
(B) Select and write the correct alternative from the choices given below: [4×1] 
 (i) An alkyl isocyanide on complete reduction gives :  
  (a) Primary amine.  
  (b) Secondary amine.  
  (c) Tertiary amine.  
  (d) Carboxylic acid.  
 (ii) For a spontaneous reaction E
o
cell and ?G
o
 will be respectively:  
  (a) -ve and -ve  
  (b) -ve and +ve  
  (c) +ve and -ve  
  (d) +ve and +ve .  
 (iii) Which of the following pairs of transition elements have exceptional 
electronic configuration? 
 
  (a) Sc and Cu  
  (b) Fe and Ni  
  (c) Cr and Cu  
  (d) Mn and Zn 
 
 
 
 
Page 3


------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
1 
CHEMISTRY PAPER  1 
(THEORY) 
------------------------------------------------------------------------------------------------ 
Maximum Marks: 70 
Time Allowed: Three hours 
(Candidates are allowed additional 15 minutes for only reading the paper. 
They must NOT start writing during this time). 
---------------------------------------------------------------------------------------------------------------- 
This paper is divided into four sections – A, B, C and D. 
Answer all questions. 
Section A consists of one question having sub-parts of one mark each. 
Section B consists of ten questions of two marks each. 
Section C consists of seven questions of three marks each, and 
Section D consists of three questions of five marks each. 
Internal choices have been provided in one question each in Section B, 
Section C and Section D. 
All working, including rough work, should be done on the same sheet as, and 
adjacent to the rest of the answer. 
The intended marks for questions or parts of questions are given in brackets [ ]. 
Balanced equations must be given wherever possible and diagrams where they 
are helpful. 
When solving numerical problems, all essential working must be shown. 
In working out problems, use the following data: 
Gas constant R = 1 ?987 cal deg
-1
 mol
-1
 = 8 ?314 JK
-1
 mol
-1
  
= 0 ?0821 dm
3
 atm K
-1
mol
-1
 
1 l  atm = 1 dm
3
 atm  = 101 ?3 J.  1 Faraday = 96500 coulombs.   
Avogadro’s number = 6 ?023 ?10
23
. 
---------------------------------------------------------------------------------------------------------------- 
SECTION A – 14 MARKS 
Question 1  
(A) Fill in the blanks by choosing the appropriate word(s) from those given in the 
brackets: 
[two, Williamson’s synthesis, three, anisole, toluene, Friedel-Crafts alkylation, 
iodoform, sec
-1
, mol
-1
L sec
-1
, Lewis base, acetone, Lewis acid, chloroform, 
formaldehyde] 
[4×1] 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
2 
 (i) Sodium phenoxide reacts with methyl chloride to give _______. The 
reaction is known as ________. 
 
 (ii) When the concentration of a reactant of first order reaction is tripled, the 
rate of reaction becomes ________ times. The unit of rate constant (k) for 
the first order reaction is ________. 
 
 (iii) In coordination complexes, the central metal atom or ion behaves as 
________ and the ligands behave as ________. 
 
 (iv) Calcium acetate on dry distillation gives ________ which gives _______ 
on heating with iodine and alkali. 
 
(B) Select and write the correct alternative from the choices given below: [4×1] 
 (i) An alkyl isocyanide on complete reduction gives :  
  (a) Primary amine.  
  (b) Secondary amine.  
  (c) Tertiary amine.  
  (d) Carboxylic acid.  
 (ii) For a spontaneous reaction E
o
cell and ?G
o
 will be respectively:  
  (a) -ve and -ve  
  (b) -ve and +ve  
  (c) +ve and -ve  
  (d) +ve and +ve .  
 (iii) Which of the following pairs of transition elements have exceptional 
electronic configuration? 
 
  (a) Sc and Cu  
  (b) Fe and Ni  
  (c) Cr and Cu  
  (d) Mn and Zn 
 
 
 
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
3 
 (iv) For a first order reaction, when 100g of the reactant is taken, 75g of the 
reactant reacts in 8 minutes. If 200g of the same reactant is taken, in how 
much time 150g of the reactant will react? 
 
  (a) 8 minutes  
  (b) 16 minutes  
  (c) 20 minutes  
  (d) 24 minutes.  
(C) Match the following: [4×1] 
 (i) Phenol (a) Osmotic pressure  
 (ii) Ethylenediamine (b) Zwitter ion  
 (iii) Colligative property (c) Neutral FeCl3 solution  
 (iv) Amino acid (d) Bidentate ligand.  
(D)  [2×1] 
 (i) Assertion: Specific conductance of all electrolytes decreases on dilution. 
Reason: On dilution, number of ions per unit volume decreases. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 (ii) Assertion: Nitration of chlorobenzene leads to the formation of m-nitro 
chlorobenzene. 
Reason: Nitro (-NO2) group is a m-directing group. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 
 
Page 4


------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
1 
CHEMISTRY PAPER  1 
(THEORY) 
------------------------------------------------------------------------------------------------ 
Maximum Marks: 70 
Time Allowed: Three hours 
(Candidates are allowed additional 15 minutes for only reading the paper. 
They must NOT start writing during this time). 
---------------------------------------------------------------------------------------------------------------- 
This paper is divided into four sections – A, B, C and D. 
Answer all questions. 
Section A consists of one question having sub-parts of one mark each. 
Section B consists of ten questions of two marks each. 
Section C consists of seven questions of three marks each, and 
Section D consists of three questions of five marks each. 
Internal choices have been provided in one question each in Section B, 
Section C and Section D. 
All working, including rough work, should be done on the same sheet as, and 
adjacent to the rest of the answer. 
The intended marks for questions or parts of questions are given in brackets [ ]. 
Balanced equations must be given wherever possible and diagrams where they 
are helpful. 
When solving numerical problems, all essential working must be shown. 
In working out problems, use the following data: 
Gas constant R = 1 ?987 cal deg
-1
 mol
-1
 = 8 ?314 JK
-1
 mol
-1
  
= 0 ?0821 dm
3
 atm K
-1
mol
-1
 
1 l  atm = 1 dm
3
 atm  = 101 ?3 J.  1 Faraday = 96500 coulombs.   
Avogadro’s number = 6 ?023 ?10
23
. 
---------------------------------------------------------------------------------------------------------------- 
SECTION A – 14 MARKS 
Question 1  
(A) Fill in the blanks by choosing the appropriate word(s) from those given in the 
brackets: 
[two, Williamson’s synthesis, three, anisole, toluene, Friedel-Crafts alkylation, 
iodoform, sec
-1
, mol
-1
L sec
-1
, Lewis base, acetone, Lewis acid, chloroform, 
formaldehyde] 
[4×1] 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
2 
 (i) Sodium phenoxide reacts with methyl chloride to give _______. The 
reaction is known as ________. 
 
 (ii) When the concentration of a reactant of first order reaction is tripled, the 
rate of reaction becomes ________ times. The unit of rate constant (k) for 
the first order reaction is ________. 
 
 (iii) In coordination complexes, the central metal atom or ion behaves as 
________ and the ligands behave as ________. 
 
 (iv) Calcium acetate on dry distillation gives ________ which gives _______ 
on heating with iodine and alkali. 
 
(B) Select and write the correct alternative from the choices given below: [4×1] 
 (i) An alkyl isocyanide on complete reduction gives :  
  (a) Primary amine.  
  (b) Secondary amine.  
  (c) Tertiary amine.  
  (d) Carboxylic acid.  
 (ii) For a spontaneous reaction E
o
cell and ?G
o
 will be respectively:  
  (a) -ve and -ve  
  (b) -ve and +ve  
  (c) +ve and -ve  
  (d) +ve and +ve .  
 (iii) Which of the following pairs of transition elements have exceptional 
electronic configuration? 
 
  (a) Sc and Cu  
  (b) Fe and Ni  
  (c) Cr and Cu  
  (d) Mn and Zn 
 
 
 
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
3 
 (iv) For a first order reaction, when 100g of the reactant is taken, 75g of the 
reactant reacts in 8 minutes. If 200g of the same reactant is taken, in how 
much time 150g of the reactant will react? 
 
  (a) 8 minutes  
  (b) 16 minutes  
  (c) 20 minutes  
  (d) 24 minutes.  
(C) Match the following: [4×1] 
 (i) Phenol (a) Osmotic pressure  
 (ii) Ethylenediamine (b) Zwitter ion  
 (iii) Colligative property (c) Neutral FeCl3 solution  
 (iv) Amino acid (d) Bidentate ligand.  
(D)  [2×1] 
 (i) Assertion: Specific conductance of all electrolytes decreases on dilution. 
Reason: On dilution, number of ions per unit volume decreases. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 (ii) Assertion: Nitration of chlorobenzene leads to the formation of m-nitro 
chlorobenzene. 
Reason: Nitro (-NO2) group is a m-directing group. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
4 
SECTION B – 20 MARKS 
Question 2 [2] 
The osmotic pressure of 20g haemoglobin in 500ml of solution is 0·016atm at 25
o
C. 
Calculate the molecular mass of haemoglobin. 
 
 
 
Question 3 [2] 
Give reason for the following:  
(i) Transition metals form large number of complex compounds.  
(ii) Transition elements show variable oxidation states.  
 
 
Question 4 [2] 
Identify compounds  [A] and [B] in the following reactions.  
(i) 
                                                               +HOH/H
+
 
CH3Br    +    KCN(alc)                   [A]                    [B] 
                                                        
(complete hydrolysis)
 
 
(ii) 
                                                         0-5
o
C                       Cu2Cl2/HCl 
C6H5NH2   +     HNO2    +    HCl                 [A]                            [B] 
 
 
 
Question 5 [2] 
State reasons for the following: 
 
(i) Ethylamine is soluble in water whereas aniline is not soluble in water.  
(ii) Aliphatic amines are stronger bases than aromatic amines.  
 
 
 Question 6 [2] 
Calculate the standard free energy change (?G
o
) for the following chemical 
reaction: 
 
(i) Cd(s)    +    2Ag
+
                             Cd
2+
    +    2Ag(s)      
(ii) E
o
Cd
2+
/Cd    =  - 0·40V,     E
o
Ag
+
/Ag   =   +0·80V  
 
Page 5


------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
1 
CHEMISTRY PAPER  1 
(THEORY) 
------------------------------------------------------------------------------------------------ 
Maximum Marks: 70 
Time Allowed: Three hours 
(Candidates are allowed additional 15 minutes for only reading the paper. 
They must NOT start writing during this time). 
---------------------------------------------------------------------------------------------------------------- 
This paper is divided into four sections – A, B, C and D. 
Answer all questions. 
Section A consists of one question having sub-parts of one mark each. 
Section B consists of ten questions of two marks each. 
Section C consists of seven questions of three marks each, and 
Section D consists of three questions of five marks each. 
Internal choices have been provided in one question each in Section B, 
Section C and Section D. 
All working, including rough work, should be done on the same sheet as, and 
adjacent to the rest of the answer. 
The intended marks for questions or parts of questions are given in brackets [ ]. 
Balanced equations must be given wherever possible and diagrams where they 
are helpful. 
When solving numerical problems, all essential working must be shown. 
In working out problems, use the following data: 
Gas constant R = 1 ?987 cal deg
-1
 mol
-1
 = 8 ?314 JK
-1
 mol
-1
  
= 0 ?0821 dm
3
 atm K
-1
mol
-1
 
1 l  atm = 1 dm
3
 atm  = 101 ?3 J.  1 Faraday = 96500 coulombs.   
Avogadro’s number = 6 ?023 ?10
23
. 
---------------------------------------------------------------------------------------------------------------- 
SECTION A – 14 MARKS 
Question 1  
(A) Fill in the blanks by choosing the appropriate word(s) from those given in the 
brackets: 
[two, Williamson’s synthesis, three, anisole, toluene, Friedel-Crafts alkylation, 
iodoform, sec
-1
, mol
-1
L sec
-1
, Lewis base, acetone, Lewis acid, chloroform, 
formaldehyde] 
[4×1] 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
2 
 (i) Sodium phenoxide reacts with methyl chloride to give _______. The 
reaction is known as ________. 
 
 (ii) When the concentration of a reactant of first order reaction is tripled, the 
rate of reaction becomes ________ times. The unit of rate constant (k) for 
the first order reaction is ________. 
 
 (iii) In coordination complexes, the central metal atom or ion behaves as 
________ and the ligands behave as ________. 
 
 (iv) Calcium acetate on dry distillation gives ________ which gives _______ 
on heating with iodine and alkali. 
 
(B) Select and write the correct alternative from the choices given below: [4×1] 
 (i) An alkyl isocyanide on complete reduction gives :  
  (a) Primary amine.  
  (b) Secondary amine.  
  (c) Tertiary amine.  
  (d) Carboxylic acid.  
 (ii) For a spontaneous reaction E
o
cell and ?G
o
 will be respectively:  
  (a) -ve and -ve  
  (b) -ve and +ve  
  (c) +ve and -ve  
  (d) +ve and +ve .  
 (iii) Which of the following pairs of transition elements have exceptional 
electronic configuration? 
 
  (a) Sc and Cu  
  (b) Fe and Ni  
  (c) Cr and Cu  
  (d) Mn and Zn 
 
 
 
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
3 
 (iv) For a first order reaction, when 100g of the reactant is taken, 75g of the 
reactant reacts in 8 minutes. If 200g of the same reactant is taken, in how 
much time 150g of the reactant will react? 
 
  (a) 8 minutes  
  (b) 16 minutes  
  (c) 20 minutes  
  (d) 24 minutes.  
(C) Match the following: [4×1] 
 (i) Phenol (a) Osmotic pressure  
 (ii) Ethylenediamine (b) Zwitter ion  
 (iii) Colligative property (c) Neutral FeCl3 solution  
 (iv) Amino acid (d) Bidentate ligand.  
(D)  [2×1] 
 (i) Assertion: Specific conductance of all electrolytes decreases on dilution. 
Reason: On dilution, number of ions per unit volume decreases. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 (ii) Assertion: Nitration of chlorobenzene leads to the formation of m-nitro 
chlorobenzene. 
Reason: Nitro (-NO2) group is a m-directing group. 
 
  (a) Both assertion and reason are true and reason is the correct 
explanation of assertion. 
 
  (b) Both assertion and reason are true but reason is not the correct 
explanation for assertion. 
 
  (c) Assertion is true but reason is false.  
  (d) Assertion is false but reason is true.  
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
4 
SECTION B – 20 MARKS 
Question 2 [2] 
The osmotic pressure of 20g haemoglobin in 500ml of solution is 0·016atm at 25
o
C. 
Calculate the molecular mass of haemoglobin. 
 
 
 
Question 3 [2] 
Give reason for the following:  
(i) Transition metals form large number of complex compounds.  
(ii) Transition elements show variable oxidation states.  
 
 
Question 4 [2] 
Identify compounds  [A] and [B] in the following reactions.  
(i) 
                                                               +HOH/H
+
 
CH3Br    +    KCN(alc)                   [A]                    [B] 
                                                        
(complete hydrolysis)
 
 
(ii) 
                                                         0-5
o
C                       Cu2Cl2/HCl 
C6H5NH2   +     HNO2    +    HCl                 [A]                            [B] 
 
 
 
Question 5 [2] 
State reasons for the following: 
 
(i) Ethylamine is soluble in water whereas aniline is not soluble in water.  
(ii) Aliphatic amines are stronger bases than aromatic amines.  
 
 
 Question 6 [2] 
Calculate the standard free energy change (?G
o
) for the following chemical 
reaction: 
 
(i) Cd(s)    +    2Ag
+
                             Cd
2+
    +    2Ag(s)      
(ii) E
o
Cd
2+
/Cd    =  - 0·40V,     E
o
Ag
+
/Ag   =   +0·80V  
 
 
------------------------------------------------------------------------------------------------------------------- 
ISC SPECIMEN QUESTION PAPER 2023 
5 
Question 7 [2] 
Complete and balance the following chemical equations:  
(i) KMnO4   +   H2SO4   +   FeSO4           ______ + _____ + _____ + _____  
(ii) K2Cr2O7  +  KI  +  H2SO4               ______ + _____ + _____ + _____  
 
 
Question 8 [2] 
(i) How will the following be obtained?  (Give chemical equation)  
 (a) Picric acid from phenol  
 (b) Ethanol from formaldehyde  
 OR  
(ii) Write the chemical equations for the dehydration of ethanol with conc. H2SO4 at 
140
o
C and 170
o
C. 
 
 
 
Question 9 [2] 
A solution of urea in water has boiling point 100·128
o
C. Calculate the freezing point of 
the same solution. Molal constants for water are Kb = 0·512 K kg mol
-1 
and                              
Kf  = 1·86 K kg mol
-1
 respectively. 
 
 
 
Question 10 [2] 
Give one chemical test for each to distinguish between the following pair of compounds.  
(i) Formaldehyde and acetic acid  
(ii) Acetaldehyde and acetone  
 
 
Question 11 [2] 
Why are Zn, Cd and Hg not regarded as transition elements?