Chemistry: Sample Question Paper- 3, Class 12 | Chemistry for Grade 12 PDF Download

 Page 1


  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 3 
 
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. Use of a calculator is not allowed.  
 
Section A 
1. What is a copolymer? 
 
2. Why are amorphous solids sometimes called super cooled liquids?  
 
OR 
 
        Frenkel defect is not found in halides of alkali metals. Why? 
 
3. Name a reagent required to oxidise primary alcohol to aldehyde in good yield.  
 
4. Can a bimolecular reaction ever be a first-order reaction?  State the condition under 
which it is possible. 
 
5. P4O10 is a well-known dehydrating agent but cannot be used for drying ammonia. Why?                                                                                                                                
 
OR 
 
       Arrange the halo acids in the increasing order of their acidic character. 
 
Section B 
 
6. Define the following terms: 
(a) Mole fraction 
(b) van’t Hoff factor 
 
OR 
 
Derive the relationship between mole fraction and vapour pressure of a component of an 
ideal solution in the liquid phase and vapour phase. 
Page 2


  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 3 
 
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. Use of a calculator is not allowed.  
 
Section A 
1. What is a copolymer? 
 
2. Why are amorphous solids sometimes called super cooled liquids?  
 
OR 
 
        Frenkel defect is not found in halides of alkali metals. Why? 
 
3. Name a reagent required to oxidise primary alcohol to aldehyde in good yield.  
 
4. Can a bimolecular reaction ever be a first-order reaction?  State the condition under 
which it is possible. 
 
5. P4O10 is a well-known dehydrating agent but cannot be used for drying ammonia. Why?                                                                                                                                
 
OR 
 
       Arrange the halo acids in the increasing order of their acidic character. 
 
Section B 
 
6. Define the following terms: 
(a) Mole fraction 
(b) van’t Hoff factor 
 
OR 
 
Derive the relationship between mole fraction and vapour pressure of a component of an 
ideal solution in the liquid phase and vapour phase. 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
7. In a cell reaction, the equilibrium constant Kc is less than one.  
(a) Is E
?
 for the cell positive or negative? 
(b) What will be the value of Kc if E
?
cell = 0? 
 
8. Calculate the half-life of a first-order reaction whose rate constant is 200 s
-1
. 
 
9. Find the oxidation states of halogens in the following: 
(a) Cl2O 
(b) KBrO3 
 
10. Give a chemical test to distinguish between methanol and ethanol. 
 
11. Give IUPAC names of the following:  
(a)  
         
 
(b) C6H5NHCH3 
OR 
 
Illustrate the following with an example reaction: 
(a) Ambident nucleophile 
(b) Hinsberg test 
 
12.  
(a) What is the role of benzoyl peroxide in the polymerisation of ethene? 
(b) What are LDPE and HDPE? How are they prepared? 
 
Section C 
 
13. An element has a body-centred cubic structure with a cell edge of 288 pm. The density 
of the element is 7.2 g cm
-3
. Calculate the number of atoms present in 208 g of the 
element. 
 
14. An aqueous solution of glucose is made by dissolving 10 g of glucose (C6H12O6) in 90 g 
of water at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mmHg, what 
would be the vapour pressure of the solution? 
 
OR 
 
Calculate the mass of a non-volatile solute (molar mass 40 g mol
-1
) which should be 
dissolved in 114 g octane to reduce its vapour pressure to 80%. 
 
15. The reaction SO2Cl2  SO2 + Cl2 is a first-order reaction with half-life of 3.15 × 10
4
 s at 
320
o
C. What percentage of SO2Cl2 would be decomposed on heating at 320
o
C for 90 
minutes? 
?
Page 3


  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 3 
 
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. Use of a calculator is not allowed.  
 
Section A 
1. What is a copolymer? 
 
2. Why are amorphous solids sometimes called super cooled liquids?  
 
OR 
 
        Frenkel defect is not found in halides of alkali metals. Why? 
 
3. Name a reagent required to oxidise primary alcohol to aldehyde in good yield.  
 
4. Can a bimolecular reaction ever be a first-order reaction?  State the condition under 
which it is possible. 
 
5. P4O10 is a well-known dehydrating agent but cannot be used for drying ammonia. Why?                                                                                                                                
 
OR 
 
       Arrange the halo acids in the increasing order of their acidic character. 
 
Section B 
 
6. Define the following terms: 
(a) Mole fraction 
(b) van’t Hoff factor 
 
OR 
 
Derive the relationship between mole fraction and vapour pressure of a component of an 
ideal solution in the liquid phase and vapour phase. 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
7. In a cell reaction, the equilibrium constant Kc is less than one.  
(a) Is E
?
 for the cell positive or negative? 
(b) What will be the value of Kc if E
?
cell = 0? 
 
8. Calculate the half-life of a first-order reaction whose rate constant is 200 s
-1
. 
 
9. Find the oxidation states of halogens in the following: 
(a) Cl2O 
(b) KBrO3 
 
10. Give a chemical test to distinguish between methanol and ethanol. 
 
11. Give IUPAC names of the following:  
(a)  
         
 
(b) C6H5NHCH3 
OR 
 
Illustrate the following with an example reaction: 
(a) Ambident nucleophile 
(b) Hinsberg test 
 
12.  
(a) What is the role of benzoyl peroxide in the polymerisation of ethene? 
(b) What are LDPE and HDPE? How are they prepared? 
 
Section C 
 
13. An element has a body-centred cubic structure with a cell edge of 288 pm. The density 
of the element is 7.2 g cm
-3
. Calculate the number of atoms present in 208 g of the 
element. 
 
14. An aqueous solution of glucose is made by dissolving 10 g of glucose (C6H12O6) in 90 g 
of water at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mmHg, what 
would be the vapour pressure of the solution? 
 
OR 
 
Calculate the mass of a non-volatile solute (molar mass 40 g mol
-1
) which should be 
dissolved in 114 g octane to reduce its vapour pressure to 80%. 
 
15. The reaction SO2Cl2  SO2 + Cl2 is a first-order reaction with half-life of 3.15 × 10
4
 s at 
320
o
C. What percentage of SO2Cl2 would be decomposed on heating at 320
o
C for 90 
minutes? 
?
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
16.  How do size of particles of adsorbent, pressure of gas and prevailing temperature 
influence the extent of adsorption of a gas on a solid? 
 
17. An oxide ore of a metal contains oxides of Fe, Si and Ti as impurities. It is concentrated 
using a chemical method and further reduced using electrolysis. The metal is widely 
used as packing material for household purposes. Identify the metal, ore and give 
equations involved in its concentration.  
 
OR 
Explain: 
(a) Roasting 
(b) Calcination 
 
18. Calculate the number of unpaired electrons in the following gaseous state ions:  
Mn
2+
, Ce
3+
, V
3+
 and Fe
2+
 
 
 
19. Write the IUPAC names of the following compounds: 
(a) [Pt(NH3)2Cl(NO2)] 
(b) K3[Al(C2O4)3] 
(c) [Ni(CO)4] 
 
20. Identify chiral molecules in each of the following pairs of compounds: 
(a)  
 
 
(b)  
 
 
(c)  
 
OR 
 
 
Page 4


  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 3 
 
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. Use of a calculator is not allowed.  
 
Section A 
1. What is a copolymer? 
 
2. Why are amorphous solids sometimes called super cooled liquids?  
 
OR 
 
        Frenkel defect is not found in halides of alkali metals. Why? 
 
3. Name a reagent required to oxidise primary alcohol to aldehyde in good yield.  
 
4. Can a bimolecular reaction ever be a first-order reaction?  State the condition under 
which it is possible. 
 
5. P4O10 is a well-known dehydrating agent but cannot be used for drying ammonia. Why?                                                                                                                                
 
OR 
 
       Arrange the halo acids in the increasing order of their acidic character. 
 
Section B 
 
6. Define the following terms: 
(a) Mole fraction 
(b) van’t Hoff factor 
 
OR 
 
Derive the relationship between mole fraction and vapour pressure of a component of an 
ideal solution in the liquid phase and vapour phase. 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
7. In a cell reaction, the equilibrium constant Kc is less than one.  
(a) Is E
?
 for the cell positive or negative? 
(b) What will be the value of Kc if E
?
cell = 0? 
 
8. Calculate the half-life of a first-order reaction whose rate constant is 200 s
-1
. 
 
9. Find the oxidation states of halogens in the following: 
(a) Cl2O 
(b) KBrO3 
 
10. Give a chemical test to distinguish between methanol and ethanol. 
 
11. Give IUPAC names of the following:  
(a)  
         
 
(b) C6H5NHCH3 
OR 
 
Illustrate the following with an example reaction: 
(a) Ambident nucleophile 
(b) Hinsberg test 
 
12.  
(a) What is the role of benzoyl peroxide in the polymerisation of ethene? 
(b) What are LDPE and HDPE? How are they prepared? 
 
Section C 
 
13. An element has a body-centred cubic structure with a cell edge of 288 pm. The density 
of the element is 7.2 g cm
-3
. Calculate the number of atoms present in 208 g of the 
element. 
 
14. An aqueous solution of glucose is made by dissolving 10 g of glucose (C6H12O6) in 90 g 
of water at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mmHg, what 
would be the vapour pressure of the solution? 
 
OR 
 
Calculate the mass of a non-volatile solute (molar mass 40 g mol
-1
) which should be 
dissolved in 114 g octane to reduce its vapour pressure to 80%. 
 
15. The reaction SO2Cl2  SO2 + Cl2 is a first-order reaction with half-life of 3.15 × 10
4
 s at 
320
o
C. What percentage of SO2Cl2 would be decomposed on heating at 320
o
C for 90 
minutes? 
?
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
16.  How do size of particles of adsorbent, pressure of gas and prevailing temperature 
influence the extent of adsorption of a gas on a solid? 
 
17. An oxide ore of a metal contains oxides of Fe, Si and Ti as impurities. It is concentrated 
using a chemical method and further reduced using electrolysis. The metal is widely 
used as packing material for household purposes. Identify the metal, ore and give 
equations involved in its concentration.  
 
OR 
Explain: 
(a) Roasting 
(b) Calcination 
 
18. Calculate the number of unpaired electrons in the following gaseous state ions:  
Mn
2+
, Ce
3+
, V
3+
 and Fe
2+
 
 
 
19. Write the IUPAC names of the following compounds: 
(a) [Pt(NH3)2Cl(NO2)] 
(b) K3[Al(C2O4)3] 
(c) [Ni(CO)4] 
 
20. Identify chiral molecules in each of the following pairs of compounds: 
(a)  
 
 
(b)  
 
 
(c)  
 
OR 
 
 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
       Write the structures of the products of the following reactions: 
(a) 
2
H O/H
32
CH CH CH
?
? ? ? ? ? ? 
(b)  
 
 
(c) 
4
NaBH
3 2 3
CH CH CH(CH ) CHO ? ? ? ? ? ? ? 
 
21. Write the structures of the following organic halogen compounds: 
(a) 2-chloro-3-methyl pentane 
(b) p-Bromochlorobenzene 
(c) Perfluorobenzene 
 
22. Arrange the following: 
(a) In the decreasing order of pKb values: 
       C2H5NH2, C6H5NHCH3, (C2H5)2NH and C6H5NH2 
(b) In the increasing order of basic strength: 
       C6H5NH2, C6H5NHCH3, (C2H5)2NH and CH3NH2 
(c) In the increasing order of boiling point: 
        C2H5OH, (CH3)2NH, C2H5NH2 
 
23.  
(a) Amylose and cellulose are both straight chain polysaccharides containing only D-
glucose units. 
(b) What is the structural difference between the two? 
(c) Why does milk get coagulated when lemon juice is added to it? 
 
24. What is paracetamol? Give its structure. Mention two medicinal effects it can have on 
the human body. 
OR 
 
        Write a note on artificial sweetening agents. 
 
Section D 
 
25. The degree of dissociation of Ca(NO3)2 in dilute aqueous solution containing 7.0 g of salt 
per 100 g water at 100
o
C is 70%. If the vapour pressure of water at 100
o
C is 760 mmHg, 
calculate the vapour pressure of the solution. 
 
OR 
 
The molar volume of liquid benzene (density = 0.877 gmL
-1
) increases by a factor of 2750 
as it vaporises at 20
o
C and that of liquid toluene (density = 0.867 g ml
-1
) increases by a 
factor of 7720 at 20
o
C. A solution of benzene and toluene at 20
o
C has a vapour pressure 
of 46.0 torr. Find the mole fraction of benzene in the vapour above the solution.                                                                                       
Page 5


  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
CBSE 
Class XII Chemistry   
Sample Paper 3 
 
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. Use of a calculator is not allowed.  
 
Section A 
1. What is a copolymer? 
 
2. Why are amorphous solids sometimes called super cooled liquids?  
 
OR 
 
        Frenkel defect is not found in halides of alkali metals. Why? 
 
3. Name a reagent required to oxidise primary alcohol to aldehyde in good yield.  
 
4. Can a bimolecular reaction ever be a first-order reaction?  State the condition under 
which it is possible. 
 
5. P4O10 is a well-known dehydrating agent but cannot be used for drying ammonia. Why?                                                                                                                                
 
OR 
 
       Arrange the halo acids in the increasing order of their acidic character. 
 
Section B 
 
6. Define the following terms: 
(a) Mole fraction 
(b) van’t Hoff factor 
 
OR 
 
Derive the relationship between mole fraction and vapour pressure of a component of an 
ideal solution in the liquid phase and vapour phase. 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
7. In a cell reaction, the equilibrium constant Kc is less than one.  
(a) Is E
?
 for the cell positive or negative? 
(b) What will be the value of Kc if E
?
cell = 0? 
 
8. Calculate the half-life of a first-order reaction whose rate constant is 200 s
-1
. 
 
9. Find the oxidation states of halogens in the following: 
(a) Cl2O 
(b) KBrO3 
 
10. Give a chemical test to distinguish between methanol and ethanol. 
 
11. Give IUPAC names of the following:  
(a)  
         
 
(b) C6H5NHCH3 
OR 
 
Illustrate the following with an example reaction: 
(a) Ambident nucleophile 
(b) Hinsberg test 
 
12.  
(a) What is the role of benzoyl peroxide in the polymerisation of ethene? 
(b) What are LDPE and HDPE? How are they prepared? 
 
Section C 
 
13. An element has a body-centred cubic structure with a cell edge of 288 pm. The density 
of the element is 7.2 g cm
-3
. Calculate the number of atoms present in 208 g of the 
element. 
 
14. An aqueous solution of glucose is made by dissolving 10 g of glucose (C6H12O6) in 90 g 
of water at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mmHg, what 
would be the vapour pressure of the solution? 
 
OR 
 
Calculate the mass of a non-volatile solute (molar mass 40 g mol
-1
) which should be 
dissolved in 114 g octane to reduce its vapour pressure to 80%. 
 
15. The reaction SO2Cl2  SO2 + Cl2 is a first-order reaction with half-life of 3.15 × 10
4
 s at 
320
o
C. What percentage of SO2Cl2 would be decomposed on heating at 320
o
C for 90 
minutes? 
?
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
16.  How do size of particles of adsorbent, pressure of gas and prevailing temperature 
influence the extent of adsorption of a gas on a solid? 
 
17. An oxide ore of a metal contains oxides of Fe, Si and Ti as impurities. It is concentrated 
using a chemical method and further reduced using electrolysis. The metal is widely 
used as packing material for household purposes. Identify the metal, ore and give 
equations involved in its concentration.  
 
OR 
Explain: 
(a) Roasting 
(b) Calcination 
 
18. Calculate the number of unpaired electrons in the following gaseous state ions:  
Mn
2+
, Ce
3+
, V
3+
 and Fe
2+
 
 
 
19. Write the IUPAC names of the following compounds: 
(a) [Pt(NH3)2Cl(NO2)] 
(b) K3[Al(C2O4)3] 
(c) [Ni(CO)4] 
 
20. Identify chiral molecules in each of the following pairs of compounds: 
(a)  
 
 
(b)  
 
 
(c)  
 
OR 
 
 
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
       Write the structures of the products of the following reactions: 
(a) 
2
H O/H
32
CH CH CH
?
? ? ? ? ? ? 
(b)  
 
 
(c) 
4
NaBH
3 2 3
CH CH CH(CH ) CHO ? ? ? ? ? ? ? 
 
21. Write the structures of the following organic halogen compounds: 
(a) 2-chloro-3-methyl pentane 
(b) p-Bromochlorobenzene 
(c) Perfluorobenzene 
 
22. Arrange the following: 
(a) In the decreasing order of pKb values: 
       C2H5NH2, C6H5NHCH3, (C2H5)2NH and C6H5NH2 
(b) In the increasing order of basic strength: 
       C6H5NH2, C6H5NHCH3, (C2H5)2NH and CH3NH2 
(c) In the increasing order of boiling point: 
        C2H5OH, (CH3)2NH, C2H5NH2 
 
23.  
(a) Amylose and cellulose are both straight chain polysaccharides containing only D-
glucose units. 
(b) What is the structural difference between the two? 
(c) Why does milk get coagulated when lemon juice is added to it? 
 
24. What is paracetamol? Give its structure. Mention two medicinal effects it can have on 
the human body. 
OR 
 
        Write a note on artificial sweetening agents. 
 
Section D 
 
25. The degree of dissociation of Ca(NO3)2 in dilute aqueous solution containing 7.0 g of salt 
per 100 g water at 100
o
C is 70%. If the vapour pressure of water at 100
o
C is 760 mmHg, 
calculate the vapour pressure of the solution. 
 
OR 
 
The molar volume of liquid benzene (density = 0.877 gmL
-1
) increases by a factor of 2750 
as it vaporises at 20
o
C and that of liquid toluene (density = 0.867 g ml
-1
) increases by a 
factor of 7720 at 20
o
C. A solution of benzene and toluene at 20
o
C has a vapour pressure 
of 46.0 torr. Find the mole fraction of benzene in the vapour above the solution.                                                                                       
  
 
CBSE XII  |  Chemistry  
Sample Paper 3 
 
     
26. Give reasons:  
(a) Cr
2+
 is a strong reducing agent, whereas Mn
2+
 is not. (Cr = 24, Mn = 25) 
(b) The transition metal ions such as Cu
+
, Ag
+
 and Sc
3+
 are colourless. 
(c) The enthalpies of atomisation of transition metals of the 3d series do not follow a 
regular trend throughout the series. 
(d) The radius of Fe
2+
 (Z = 26) is less than that of Mn
2+
 (Z = 25). 
(e) Chemistry of the actinoids is more complicated than that of the lanthanoids. 
 
OR 
 
(a)  Write the chemical equations involved in the following:   
 
 
(b) Use Hund’s rule to derive the electronic configuration of Ce³
+
 ion, and calculate its 
magnetic moment on the basis of the ‘spin only’ formula. 
 
27.  Complete the equations and name the reaction represented.                                
 
            
 
OR 
 
     Complete the equations:  
(i) C6H5CONH2  
(ii) C6H5COOCOCH3  
 
(iii) CH3COCl + H2O  
(iv)  
(v)  
 
?
? ? ? ? ? ?
?
   1)   FeCr O +  8Na CO +  O
4 2 2 3 2
513 K
2) 2KMnO  
4
?
2- +
3) 2CrO + H 
4
? ? ? ? ? ? ? ?
? ? ? ? ? ? ? ?
? ? ? ? ? ? ? ?
? ? ? ? ? ? ?
1.Cl /red P
2
(i)  CH COOH      
3
2. H O
2
conc. KOH
(ii) 2 HCHO    
anhy.AlCl
3
(iii) C H + CH COCl      
6 6 3
+
HO
3
(iv) RCN + SnCl + HCl A     B
2
3
HO
?
?
? ? ? ? ?
Heat
? ? ? ? ?
?
? ? ? ? ?
+
H
CH CN + H O   
32
? ? ? ? ?
heat -+
C H COO NH 
4 6 5