Chemistry: Sample Question Paper- 4, Class 12 | Sample Papers for Class 12 Medical and Non-Medical PDF Download

 Page 1


  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 4 
 
Time: 3 Hrs                                      Total Marks: 70 
_________________________________________________________________________________________________________ 
General Instructions: 
? All questions are compulsory.  
? Section A: Q.no. 1 to 5 are very short answer questions and carry 1 mark each.  
? Section B: Q.no. 6 to 12 are short answer questions and carry 2 marks each.  
? Section C: Q.no. 13 to 24 are also short answer questions and carry 3 marks each.  
? Section D: Q.no. 25 to 27 are long answer questions and carry 5 marks each.  
? There is no overall choice. However, an internal choice has been provided in two 
questions of one mark, two questions of two marks, four questions of three marks and 
all the three questions of five marks weightage. You have to attempt only one of the 
choices in such questions.  
? Use log tables if necessary. The use of a calculator is not allowed.  
 
Section A 
 
1. Which point defect in crystals does not alter the density of the relevant solid?     [1] 
 
2. Colloidal particles show zigzag motion. What is the name given to this motion? [1] 
 
OR 
Define Tyndall effect. 
 
3. What is the maximum oxidation state shown by actinoids?     [1] 
 
OR 
 
       Name the transition element which does not exhibit variation in the oxidation state in 
its compounds. 
 
4. 2, 4, 6 Trinitrophenol is soluble in aqueous Na2CO3, while phenol is not. Why?    [1] 
 
5. What are elastomers? How are they different from fibres?     [1] 
 
Section B 
 
6. State Henry’s law. Give any one of its applications.      [2] 
 
OR 
 
       What would be the molality of an aqueous solution which has a boiling point elevation 
of 1.00 K? (For H2O, kbp = 0.512 K kg mol
-1
) 
 
 
Page 2


  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 4 
 
Time: 3 Hrs                                      Total Marks: 70 
_________________________________________________________________________________________________________ 
General Instructions: 
? All questions are compulsory.  
? Section A: Q.no. 1 to 5 are very short answer questions and carry 1 mark each.  
? Section B: Q.no. 6 to 12 are short answer questions and carry 2 marks each.  
? Section C: Q.no. 13 to 24 are also short answer questions and carry 3 marks each.  
? Section D: Q.no. 25 to 27 are long answer questions and carry 5 marks each.  
? There is no overall choice. However, an internal choice has been provided in two 
questions of one mark, two questions of two marks, four questions of three marks and 
all the three questions of five marks weightage. You have to attempt only one of the 
choices in such questions.  
? Use log tables if necessary. The use of a calculator is not allowed.  
 
Section A 
 
1. Which point defect in crystals does not alter the density of the relevant solid?     [1] 
 
2. Colloidal particles show zigzag motion. What is the name given to this motion? [1] 
 
OR 
Define Tyndall effect. 
 
3. What is the maximum oxidation state shown by actinoids?     [1] 
 
OR 
 
       Name the transition element which does not exhibit variation in the oxidation state in 
its compounds. 
 
4. 2, 4, 6 Trinitrophenol is soluble in aqueous Na2CO3, while phenol is not. Why?    [1] 
 
5. What are elastomers? How are they different from fibres?     [1] 
 
Section B 
 
6. State Henry’s law. Give any one of its applications.      [2] 
 
OR 
 
       What would be the molality of an aqueous solution which has a boiling point elevation 
of 1.00 K? (For H2O, kbp = 0.512 K kg mol
-1
) 
 
 
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
7. Calculate the e.m.f. of the following cell at 298 K:       [2] 
                                      
                                             
 
8. Name the crystal system of the compound with unit cell dimensions ? = ? = 90°,  
? = 120° and a = 0.387, b = 0.387 and c = 0.504 nm.                                          
Give an example of a compound in which this type of crystal system is present.  [2] 
 
9. How will you prepare Cl2 from HCl and HCl from Cl2? Write the reactions only.  [2] 
 
10. Which of the following undergoes SN1 faster and why?                        [2] 
(a)                                (b)        
                              
 
11. Arrange the following in the increasing order of acidic character:        [2] 
HCOOH, CH2ClCOOH, CF3COOH, CCl3COOH 
 
OR 
 
Write the IUPAC name of the following: 
(a)  
 
(b)  
 
 
12. Give the names and structures of monomers of      [2] 
(a) Dacron (b) Buna–N                                                                                                    
 
Section C 
 
13. The density of mercury is 13.6 g/ml. Calculate approximately the diameter of an atom 
of mercury assuming that each atom occupies a cube of edge length equal to the 
diameter of the mercury atom.                                                                                                 [3] 
 
14. Calculate the degree of dissociation of a decimolar solution of NaCl with osmotic 
pressure of 4.6 atm at 300 K.                 [3] 
 
OR 
 
 
 
l ll l l
+ 2+
Fe(s) Fe (0.001M) H (1M) H (1atm) Pt(s)
2
?
??
l
2+
Fe Fe
E 0.44 V
Page 3


  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 4 
 
Time: 3 Hrs                                      Total Marks: 70 
_________________________________________________________________________________________________________ 
General Instructions: 
? All questions are compulsory.  
? Section A: Q.no. 1 to 5 are very short answer questions and carry 1 mark each.  
? Section B: Q.no. 6 to 12 are short answer questions and carry 2 marks each.  
? Section C: Q.no. 13 to 24 are also short answer questions and carry 3 marks each.  
? Section D: Q.no. 25 to 27 are long answer questions and carry 5 marks each.  
? There is no overall choice. However, an internal choice has been provided in two 
questions of one mark, two questions of two marks, four questions of three marks and 
all the three questions of five marks weightage. You have to attempt only one of the 
choices in such questions.  
? Use log tables if necessary. The use of a calculator is not allowed.  
 
Section A 
 
1. Which point defect in crystals does not alter the density of the relevant solid?     [1] 
 
2. Colloidal particles show zigzag motion. What is the name given to this motion? [1] 
 
OR 
Define Tyndall effect. 
 
3. What is the maximum oxidation state shown by actinoids?     [1] 
 
OR 
 
       Name the transition element which does not exhibit variation in the oxidation state in 
its compounds. 
 
4. 2, 4, 6 Trinitrophenol is soluble in aqueous Na2CO3, while phenol is not. Why?    [1] 
 
5. What are elastomers? How are they different from fibres?     [1] 
 
Section B 
 
6. State Henry’s law. Give any one of its applications.      [2] 
 
OR 
 
       What would be the molality of an aqueous solution which has a boiling point elevation 
of 1.00 K? (For H2O, kbp = 0.512 K kg mol
-1
) 
 
 
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
7. Calculate the e.m.f. of the following cell at 298 K:       [2] 
                                      
                                             
 
8. Name the crystal system of the compound with unit cell dimensions ? = ? = 90°,  
? = 120° and a = 0.387, b = 0.387 and c = 0.504 nm.                                          
Give an example of a compound in which this type of crystal system is present.  [2] 
 
9. How will you prepare Cl2 from HCl and HCl from Cl2? Write the reactions only.  [2] 
 
10. Which of the following undergoes SN1 faster and why?                        [2] 
(a)                                (b)        
                              
 
11. Arrange the following in the increasing order of acidic character:        [2] 
HCOOH, CH2ClCOOH, CF3COOH, CCl3COOH 
 
OR 
 
Write the IUPAC name of the following: 
(a)  
 
(b)  
 
 
12. Give the names and structures of monomers of      [2] 
(a) Dacron (b) Buna–N                                                                                                    
 
Section C 
 
13. The density of mercury is 13.6 g/ml. Calculate approximately the diameter of an atom 
of mercury assuming that each atom occupies a cube of edge length equal to the 
diameter of the mercury atom.                                                                                                 [3] 
 
14. Calculate the degree of dissociation of a decimolar solution of NaCl with osmotic 
pressure of 4.6 atm at 300 K.                 [3] 
 
OR 
 
 
 
l ll l l
+ 2+
Fe(s) Fe (0.001M) H (1M) H (1atm) Pt(s)
2
?
??
l
2+
Fe Fe
E 0.44 V
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
(a) Why is the vapour pressure of a liquid constant at constant temperature? 
(b) Two liquids A and B are mixed. The resulting solution is found to be cooled. What do 
you conclude? 
(c) 2 g each of the solute A and B (mol. mass of A > B) are dissolved separately in 20 g 
each of the same solvent C. Which will show greater lowering of vapour pressure 
and why? 
 
15. The progress of a reaction, A ? nB, with time, is presented in the figure below:   [3] 
                             
Determine: 
(a) Value of n 
(b) Equilibrium constant k 
(c) Initial rate of conversion of A 
 
16. What happens when         [3] 
(a) Freshly prepared  is shaken with a little amount of dilute solution of FeCl3. 
(b) Light is passed through a colloidal solution. 
(c) Electric current is passed through a colloid.                       
 
17.  Account for the following:         [3]  
(a) Zn is not extracted from ZnO through reduction using CO. 
(b) Copper matte is put in silica lined converter 
(c) Graphite is used in electrometallurgy of Al.               
 
18.                                          [3] 
(a) An alloy A finds application in making bullets, shells etc. Name the alloy and give its 
composition.                                                                                              
(b) Which of the two is more basic: La(OH)3 or Lu(OH)3, and why? 
(c) Why does Zr (Z = 40) and Hf (Z = 72) have similar atomic radii?          
 
OR 
Account for the following: 
(a) Cr
2+
 is strongly reducing because it changes to Cr
3+
 which is more stable because 
manganese (III) is strongly oxidising. 
(b) Cobalt (III) is stable in aqueous solution, but in the presence of complexing reagents, 
it is easily oxidised. 
(c) The d
1 
configuration is very unstable in ions. 
? ?
3
Fe OH
Page 4


  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 4 
 
Time: 3 Hrs                                      Total Marks: 70 
_________________________________________________________________________________________________________ 
General Instructions: 
? All questions are compulsory.  
? Section A: Q.no. 1 to 5 are very short answer questions and carry 1 mark each.  
? Section B: Q.no. 6 to 12 are short answer questions and carry 2 marks each.  
? Section C: Q.no. 13 to 24 are also short answer questions and carry 3 marks each.  
? Section D: Q.no. 25 to 27 are long answer questions and carry 5 marks each.  
? There is no overall choice. However, an internal choice has been provided in two 
questions of one mark, two questions of two marks, four questions of three marks and 
all the three questions of five marks weightage. You have to attempt only one of the 
choices in such questions.  
? Use log tables if necessary. The use of a calculator is not allowed.  
 
Section A 
 
1. Which point defect in crystals does not alter the density of the relevant solid?     [1] 
 
2. Colloidal particles show zigzag motion. What is the name given to this motion? [1] 
 
OR 
Define Tyndall effect. 
 
3. What is the maximum oxidation state shown by actinoids?     [1] 
 
OR 
 
       Name the transition element which does not exhibit variation in the oxidation state in 
its compounds. 
 
4. 2, 4, 6 Trinitrophenol is soluble in aqueous Na2CO3, while phenol is not. Why?    [1] 
 
5. What are elastomers? How are they different from fibres?     [1] 
 
Section B 
 
6. State Henry’s law. Give any one of its applications.      [2] 
 
OR 
 
       What would be the molality of an aqueous solution which has a boiling point elevation 
of 1.00 K? (For H2O, kbp = 0.512 K kg mol
-1
) 
 
 
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
7. Calculate the e.m.f. of the following cell at 298 K:       [2] 
                                      
                                             
 
8. Name the crystal system of the compound with unit cell dimensions ? = ? = 90°,  
? = 120° and a = 0.387, b = 0.387 and c = 0.504 nm.                                          
Give an example of a compound in which this type of crystal system is present.  [2] 
 
9. How will you prepare Cl2 from HCl and HCl from Cl2? Write the reactions only.  [2] 
 
10. Which of the following undergoes SN1 faster and why?                        [2] 
(a)                                (b)        
                              
 
11. Arrange the following in the increasing order of acidic character:        [2] 
HCOOH, CH2ClCOOH, CF3COOH, CCl3COOH 
 
OR 
 
Write the IUPAC name of the following: 
(a)  
 
(b)  
 
 
12. Give the names and structures of monomers of      [2] 
(a) Dacron (b) Buna–N                                                                                                    
 
Section C 
 
13. The density of mercury is 13.6 g/ml. Calculate approximately the diameter of an atom 
of mercury assuming that each atom occupies a cube of edge length equal to the 
diameter of the mercury atom.                                                                                                 [3] 
 
14. Calculate the degree of dissociation of a decimolar solution of NaCl with osmotic 
pressure of 4.6 atm at 300 K.                 [3] 
 
OR 
 
 
 
l ll l l
+ 2+
Fe(s) Fe (0.001M) H (1M) H (1atm) Pt(s)
2
?
??
l
2+
Fe Fe
E 0.44 V
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
(a) Why is the vapour pressure of a liquid constant at constant temperature? 
(b) Two liquids A and B are mixed. The resulting solution is found to be cooled. What do 
you conclude? 
(c) 2 g each of the solute A and B (mol. mass of A > B) are dissolved separately in 20 g 
each of the same solvent C. Which will show greater lowering of vapour pressure 
and why? 
 
15. The progress of a reaction, A ? nB, with time, is presented in the figure below:   [3] 
                             
Determine: 
(a) Value of n 
(b) Equilibrium constant k 
(c) Initial rate of conversion of A 
 
16. What happens when         [3] 
(a) Freshly prepared  is shaken with a little amount of dilute solution of FeCl3. 
(b) Light is passed through a colloidal solution. 
(c) Electric current is passed through a colloid.                       
 
17.  Account for the following:         [3]  
(a) Zn is not extracted from ZnO through reduction using CO. 
(b) Copper matte is put in silica lined converter 
(c) Graphite is used in electrometallurgy of Al.               
 
18.                                          [3] 
(a) An alloy A finds application in making bullets, shells etc. Name the alloy and give its 
composition.                                                                                              
(b) Which of the two is more basic: La(OH)3 or Lu(OH)3, and why? 
(c) Why does Zr (Z = 40) and Hf (Z = 72) have similar atomic radii?          
 
OR 
Account for the following: 
(a) Cr
2+
 is strongly reducing because it changes to Cr
3+
 which is more stable because 
manganese (III) is strongly oxidising. 
(b) Cobalt (III) is stable in aqueous solution, but in the presence of complexing reagents, 
it is easily oxidised. 
(c) The d
1 
configuration is very unstable in ions. 
? ?
3
Fe OH
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
19.                                          [3] 
(a) What are ambidentate ligands? Give an example. 
(b) Write the names of the following: 
(i) K3[Cr(C2O4)3] 
(ii) Pt[(NH3)2Cl2] 
(c) Draw the structure of the cis isomer of [Co(NH3)4Cl2]
+
. 
 
20.                                             [3] 
(a) Name the reaction represented by the following equations:    
(i)  
  
(ii)  
    
                                                                                                                                                        
(b) Which of these has a higher boiling point and why?   
   Iodobenzene or chlorobenzene 
 
OR 
 
Write the structure of the main product: 
(a) Chlorination of benzene in the presence of UV light. 
(b) Propene is treated with HBr in the presence of benzoyl peroxide. 
(c) Chlorobenzene is treated with NaOH at 623 K and high pressure. 
 
21. Account for the following:         [3]                                                                                   
(a) Alcohols act as weak acids.  
(b) Phenols have smaller dipole moment than alcohols. 
(c) How can ethers be distinguished from alcohols? Give the equation involved. 
 
22.  Write short notes on          [3] 
(a) Gabriel phthalimide synthesis 
(b) Hoffmann bromamide degradation method     
 
23.                                               [3] 
(a) What happens when D-Glucose is made to react with Br2 water? Give the equation 
also.  
(b) Why are carbohydrates generally optically active?  
(c) Why can’t vitamin C be stored in the body?   
                                                                       
Page 5


  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 4 
 
Time: 3 Hrs                                      Total Marks: 70 
_________________________________________________________________________________________________________ 
General Instructions: 
? All questions are compulsory.  
? Section A: Q.no. 1 to 5 are very short answer questions and carry 1 mark each.  
? Section B: Q.no. 6 to 12 are short answer questions and carry 2 marks each.  
? Section C: Q.no. 13 to 24 are also short answer questions and carry 3 marks each.  
? Section D: Q.no. 25 to 27 are long answer questions and carry 5 marks each.  
? There is no overall choice. However, an internal choice has been provided in two 
questions of one mark, two questions of two marks, four questions of three marks and 
all the three questions of five marks weightage. You have to attempt only one of the 
choices in such questions.  
? Use log tables if necessary. The use of a calculator is not allowed.  
 
Section A 
 
1. Which point defect in crystals does not alter the density of the relevant solid?     [1] 
 
2. Colloidal particles show zigzag motion. What is the name given to this motion? [1] 
 
OR 
Define Tyndall effect. 
 
3. What is the maximum oxidation state shown by actinoids?     [1] 
 
OR 
 
       Name the transition element which does not exhibit variation in the oxidation state in 
its compounds. 
 
4. 2, 4, 6 Trinitrophenol is soluble in aqueous Na2CO3, while phenol is not. Why?    [1] 
 
5. What are elastomers? How are they different from fibres?     [1] 
 
Section B 
 
6. State Henry’s law. Give any one of its applications.      [2] 
 
OR 
 
       What would be the molality of an aqueous solution which has a boiling point elevation 
of 1.00 K? (For H2O, kbp = 0.512 K kg mol
-1
) 
 
 
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
7. Calculate the e.m.f. of the following cell at 298 K:       [2] 
                                      
                                             
 
8. Name the crystal system of the compound with unit cell dimensions ? = ? = 90°,  
? = 120° and a = 0.387, b = 0.387 and c = 0.504 nm.                                          
Give an example of a compound in which this type of crystal system is present.  [2] 
 
9. How will you prepare Cl2 from HCl and HCl from Cl2? Write the reactions only.  [2] 
 
10. Which of the following undergoes SN1 faster and why?                        [2] 
(a)                                (b)        
                              
 
11. Arrange the following in the increasing order of acidic character:        [2] 
HCOOH, CH2ClCOOH, CF3COOH, CCl3COOH 
 
OR 
 
Write the IUPAC name of the following: 
(a)  
 
(b)  
 
 
12. Give the names and structures of monomers of      [2] 
(a) Dacron (b) Buna–N                                                                                                    
 
Section C 
 
13. The density of mercury is 13.6 g/ml. Calculate approximately the diameter of an atom 
of mercury assuming that each atom occupies a cube of edge length equal to the 
diameter of the mercury atom.                                                                                                 [3] 
 
14. Calculate the degree of dissociation of a decimolar solution of NaCl with osmotic 
pressure of 4.6 atm at 300 K.                 [3] 
 
OR 
 
 
 
l ll l l
+ 2+
Fe(s) Fe (0.001M) H (1M) H (1atm) Pt(s)
2
?
??
l
2+
Fe Fe
E 0.44 V
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
(a) Why is the vapour pressure of a liquid constant at constant temperature? 
(b) Two liquids A and B are mixed. The resulting solution is found to be cooled. What do 
you conclude? 
(c) 2 g each of the solute A and B (mol. mass of A > B) are dissolved separately in 20 g 
each of the same solvent C. Which will show greater lowering of vapour pressure 
and why? 
 
15. The progress of a reaction, A ? nB, with time, is presented in the figure below:   [3] 
                             
Determine: 
(a) Value of n 
(b) Equilibrium constant k 
(c) Initial rate of conversion of A 
 
16. What happens when         [3] 
(a) Freshly prepared  is shaken with a little amount of dilute solution of FeCl3. 
(b) Light is passed through a colloidal solution. 
(c) Electric current is passed through a colloid.                       
 
17.  Account for the following:         [3]  
(a) Zn is not extracted from ZnO through reduction using CO. 
(b) Copper matte is put in silica lined converter 
(c) Graphite is used in electrometallurgy of Al.               
 
18.                                          [3] 
(a) An alloy A finds application in making bullets, shells etc. Name the alloy and give its 
composition.                                                                                              
(b) Which of the two is more basic: La(OH)3 or Lu(OH)3, and why? 
(c) Why does Zr (Z = 40) and Hf (Z = 72) have similar atomic radii?          
 
OR 
Account for the following: 
(a) Cr
2+
 is strongly reducing because it changes to Cr
3+
 which is more stable because 
manganese (III) is strongly oxidising. 
(b) Cobalt (III) is stable in aqueous solution, but in the presence of complexing reagents, 
it is easily oxidised. 
(c) The d
1 
configuration is very unstable in ions. 
? ?
3
Fe OH
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
19.                                          [3] 
(a) What are ambidentate ligands? Give an example. 
(b) Write the names of the following: 
(i) K3[Cr(C2O4)3] 
(ii) Pt[(NH3)2Cl2] 
(c) Draw the structure of the cis isomer of [Co(NH3)4Cl2]
+
. 
 
20.                                             [3] 
(a) Name the reaction represented by the following equations:    
(i)  
  
(ii)  
    
                                                                                                                                                        
(b) Which of these has a higher boiling point and why?   
   Iodobenzene or chlorobenzene 
 
OR 
 
Write the structure of the main product: 
(a) Chlorination of benzene in the presence of UV light. 
(b) Propene is treated with HBr in the presence of benzoyl peroxide. 
(c) Chlorobenzene is treated with NaOH at 623 K and high pressure. 
 
21. Account for the following:         [3]                                                                                   
(a) Alcohols act as weak acids.  
(b) Phenols have smaller dipole moment than alcohols. 
(c) How can ethers be distinguished from alcohols? Give the equation involved. 
 
22.  Write short notes on          [3] 
(a) Gabriel phthalimide synthesis 
(b) Hoffmann bromamide degradation method     
 
23.                                               [3] 
(a) What happens when D-Glucose is made to react with Br2 water? Give the equation 
also.  
(b) Why are carbohydrates generally optically active?  
(c) Why can’t vitamin C be stored in the body?   
                                                                       
  
 
CBSE XII  |  Chemistry 
Sample Paper 4 
 
     
OR 
(a) Structurally differentiate between insulin and myosin.  
(b) Two strands of DNA are complementary to each other. Account for it.  
(c) Why is sucrose known as invert sugar?  
 
24. What is saccharin and aspartame? Also give their uses.    [3] 
 
 
Section D 
25.                 [5] 
(a) Convert: 
(i) Ethanal to crotonaldehyde   
(ii) Propanoic acid to lactic acid 
(b) Draw the structure of methyl hemiacetal of formaldehyde.  
(c) How do carbonyl compounds react with sodium hydrogen sulphite? Explain giving a 
reaction.                                                                                                                                                                                                                                                            
OR 
 
Complete the equations: 
(a)    
        
(b) 
       
(c)  
        
 
(d)  
 
        
(e)