Class 11 Chemistry: CBSE Sample Question Papers - 1 (2023-24)

 Page 1


Time Allowed: 3 hours Maximum Marks: 70 
General Instructions:
1. There are 33 questions in this question paper with internal choice.
2. SECTION A consists of 16 multiple-choice questions carrying 1 mark each.
3. SECTION B consists of 5 very short answer questions carrying 2 marks each.
4. SECTION C consists of 7 short answer questions carrying 3 marks each.
5. SECTION D consists of 2 case-based questions carrying 4 marks each.
6. SECTION E consists of 3 long answer questions carrying 5 marks each.
7. All questions are compulsory.
8. The use of log tables and calculators is not allowed
Section A
a) a chemical reaction takes place b) products appear,
c) catalysts are produced. d) reactants disappear
1. Choose the most appropriate answer for the statement, "Rearrangement of atoms occurs whenever a chemical
bond breaks or is formed, when
[1]
a)
1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
 3d
10 b)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
6
 4s
2 
4p
2
c)
1s
2
 2s
2
 2p
6
 3s
2
 3p
5
 4s
1 
3d
9
 4s
2 d)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
8
 4s
2
2. An atom of an element contains 29 electrons and 35 neutrons. The electronic configuration of an element [1]
a) zero b) < 0
c) unity d) different for each element
3. The enthalpies of all elements in their standard states are: [1]
a)
n = 1,2,3..
l= 0,1,..n;
m = -l,-l+1, ..0,1..l-1, l
b)
n = 1,2,3..
l= 0,1,..n-1;
m = 0,1..l-1, l
c)
n = 1,2,3..
l= 0,1,..n
m= -l,-l+1, ..0,1
d)
n = 1, 2, 3..
l = 0, 1,.. n-1;
ml = -l,-l+1, ..0,1..l-1, l
4. According to the quantum theoretical model of an atom, each orbital is designated by three quantum numbers
labelled as n, l, and ml. The values these can take are:
[1]
Page 1 of 13
Page 2


Time Allowed: 3 hours Maximum Marks: 70 
General Instructions:
1. There are 33 questions in this question paper with internal choice.
2. SECTION A consists of 16 multiple-choice questions carrying 1 mark each.
3. SECTION B consists of 5 very short answer questions carrying 2 marks each.
4. SECTION C consists of 7 short answer questions carrying 3 marks each.
5. SECTION D consists of 2 case-based questions carrying 4 marks each.
6. SECTION E consists of 3 long answer questions carrying 5 marks each.
7. All questions are compulsory.
8. The use of log tables and calculators is not allowed
Section A
a) a chemical reaction takes place b) products appear,
c) catalysts are produced. d) reactants disappear
1. Choose the most appropriate answer for the statement, "Rearrangement of atoms occurs whenever a chemical
bond breaks or is formed, when
[1]
a)
1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
 3d
10 b)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
6
 4s
2 
4p
2
c)
1s
2
 2s
2
 2p
6
 3s
2
 3p
5
 4s
1 
3d
9
 4s
2 d)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
8
 4s
2
2. An atom of an element contains 29 electrons and 35 neutrons. The electronic configuration of an element [1]
a) zero b) < 0
c) unity d) different for each element
3. The enthalpies of all elements in their standard states are: [1]
a)
n = 1,2,3..
l= 0,1,..n;
m = -l,-l+1, ..0,1..l-1, l
b)
n = 1,2,3..
l= 0,1,..n-1;
m = 0,1..l-1, l
c)
n = 1,2,3..
l= 0,1,..n
m= -l,-l+1, ..0,1
d)
n = 1, 2, 3..
l = 0, 1,.. n-1;
ml = -l,-l+1, ..0,1..l-1, l
4. According to the quantum theoretical model of an atom, each orbital is designated by three quantum numbers
labelled as n, l, and ml. The values these can take are:
[1]
Page 1 of 13
a) one kg of bonds completely to obtain atoms
in the gas phase.
b) one mole of bonds completely to obtain
atoms in the liquid phase.
c) one kg of bonds completely to obtain atoms
in the liquid phase.
d) one mole of bonds completely to obtain
atoms in the gas phase.
5. Enthalpy of atomization is enthalpy change on breaking: [1]
a) +2, +1, 0, -1, -2 b) s, p, d
c) 0, 1, 2 d) 2l + 1
6. For azimuthal quantum number (l) = 2, the values of magnetic quantum number will be: [1]
a) +4 b) Zero
c) +8 d) -8
7. When methane is burnt in oxygen to produce CO
2
 and H
2
O the oxidation number of carbon changes by? [1]
a) *CH
3 
- CH
2 
- Br b) *CH
3 
- CH
2 
- Cl
c) *CH
3
 - CH
2
 - I d) *CH
3
 - CH
2
 - CH
3
8. In which of the following compounds the carbon marked with asterisk is expected to have greatest partial
positive charge?
[1]
a) b)
c) d)
9. Which of the following compounds is not aromatic? [1]
a) Period 3, group 1 b) Period 4, group 5
c) Period 4, group 6 d) Period 4, group 6
10. Predict the position of an element having the electronic configuration ls 
2
2s
2
2p
6
3s
2
3p
6
3d
5
4s
1
.
[1]
a) mass and its transformations to and from
other forms of energy.
b) heat and its transformations to and from
other forms of energy.
c) kinetic energy and its transformations to and
from other forms of energy.
d) potential and its transformations to and from
other forms of energy.
11. Thermodynamics is the branch of physical science concerned with [1]
a) Nitrobenzene b) Benzene
c) Toluene d) Benzoic Acid
12. Among the following compounds, the one that is most reactive towards electrophilic nitration is ________. [1]
13. Assertion: Cis- 1, 3-dihydroxycyclohexane exists in a boat conformation. 
Reason: In the boat form, there will not be hydrogen bonding between the two hydroxyl groups.
[1]
Page 2 of 13
Page 3


Time Allowed: 3 hours Maximum Marks: 70 
General Instructions:
1. There are 33 questions in this question paper with internal choice.
2. SECTION A consists of 16 multiple-choice questions carrying 1 mark each.
3. SECTION B consists of 5 very short answer questions carrying 2 marks each.
4. SECTION C consists of 7 short answer questions carrying 3 marks each.
5. SECTION D consists of 2 case-based questions carrying 4 marks each.
6. SECTION E consists of 3 long answer questions carrying 5 marks each.
7. All questions are compulsory.
8. The use of log tables and calculators is not allowed
Section A
a) a chemical reaction takes place b) products appear,
c) catalysts are produced. d) reactants disappear
1. Choose the most appropriate answer for the statement, "Rearrangement of atoms occurs whenever a chemical
bond breaks or is formed, when
[1]
a)
1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
 3d
10 b)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
6
 4s
2 
4p
2
c)
1s
2
 2s
2
 2p
6
 3s
2
 3p
5
 4s
1 
3d
9
 4s
2 d)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
8
 4s
2
2. An atom of an element contains 29 electrons and 35 neutrons. The electronic configuration of an element [1]
a) zero b) < 0
c) unity d) different for each element
3. The enthalpies of all elements in their standard states are: [1]
a)
n = 1,2,3..
l= 0,1,..n;
m = -l,-l+1, ..0,1..l-1, l
b)
n = 1,2,3..
l= 0,1,..n-1;
m = 0,1..l-1, l
c)
n = 1,2,3..
l= 0,1,..n
m= -l,-l+1, ..0,1
d)
n = 1, 2, 3..
l = 0, 1,.. n-1;
ml = -l,-l+1, ..0,1..l-1, l
4. According to the quantum theoretical model of an atom, each orbital is designated by three quantum numbers
labelled as n, l, and ml. The values these can take are:
[1]
Page 1 of 13
a) one kg of bonds completely to obtain atoms
in the gas phase.
b) one mole of bonds completely to obtain
atoms in the liquid phase.
c) one kg of bonds completely to obtain atoms
in the liquid phase.
d) one mole of bonds completely to obtain
atoms in the gas phase.
5. Enthalpy of atomization is enthalpy change on breaking: [1]
a) +2, +1, 0, -1, -2 b) s, p, d
c) 0, 1, 2 d) 2l + 1
6. For azimuthal quantum number (l) = 2, the values of magnetic quantum number will be: [1]
a) +4 b) Zero
c) +8 d) -8
7. When methane is burnt in oxygen to produce CO
2
 and H
2
O the oxidation number of carbon changes by? [1]
a) *CH
3 
- CH
2 
- Br b) *CH
3 
- CH
2 
- Cl
c) *CH
3
 - CH
2
 - I d) *CH
3
 - CH
2
 - CH
3
8. In which of the following compounds the carbon marked with asterisk is expected to have greatest partial
positive charge?
[1]
a) b)
c) d)
9. Which of the following compounds is not aromatic? [1]
a) Period 3, group 1 b) Period 4, group 5
c) Period 4, group 6 d) Period 4, group 6
10. Predict the position of an element having the electronic configuration ls 
2
2s
2
2p
6
3s
2
3p
6
3d
5
4s
1
.
[1]
a) mass and its transformations to and from
other forms of energy.
b) heat and its transformations to and from
other forms of energy.
c) kinetic energy and its transformations to and
from other forms of energy.
d) potential and its transformations to and from
other forms of energy.
11. Thermodynamics is the branch of physical science concerned with [1]
a) Nitrobenzene b) Benzene
c) Toluene d) Benzoic Acid
12. Among the following compounds, the one that is most reactive towards electrophilic nitration is ________. [1]
13. Assertion: Cis- 1, 3-dihydroxycyclohexane exists in a boat conformation. 
Reason: In the boat form, there will not be hydrogen bonding between the two hydroxyl groups.
[1]
Page 2 of 13
Section B
Section C
a) If both Assertion & Reason are true and the
reason is the correct explanation of the
assertion.
b) If both Assertion & Reason are true but the
reason is not the correct explanation of the
assertion.
c) If Assertion is true statement but Reason is
false.
d) If both Assertion and Reason are false
statements.
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
14. Assertion (A): Addition of HCl on  is faster than . 
Reason (R): Alkene that can form more stable carbocation they have higher rate of addition with HX.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
15. Assertion (A): Threshold frequency is a characteristic for a metal. 
Reason (R): Threshold frequency is the maximum frequency required for the ejection of electrons from the
metal surface.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
16. Assertion (A): The balancing of chemical equations is based on the law of conservation of mass. 
Reason (R): Total mass of reactants is equal to the total mass of products.
[1]
17. At 500 K, equilibrium constant, K
c
, for the following reaction is 5. 
 
What would be the equilibrium constant K
c
 for the reaction? 
2HI(g)  H
2
(g) + I
2
(g)
[2]
( g ) + ( g ) ? H I ( g ) 1 2 H 2 1 2 I 2 ? 18. The electronic configuration of an element is 1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
. Locate the element in the periodic table.
[2]
19. What will be the mass of one 
12
C atom in g?
[2]
20. Unsaturated compounds undergo addition reactions. Why? [2]
OR
Explain why the system are not aromatic. 
21. Give the number of electrons in the species: , H
2 
and . [2] H + 2 O + 2 22. Arrange the following sets of molecules in the decreasing order of bond angle.
i. SF
6
, CCI
4
, H
2
O, NH
3
ii. CH
4
, NH
3
, H
2
O, BF
3
[3]
Page 3 of 13
Page 4


Time Allowed: 3 hours Maximum Marks: 70 
General Instructions:
1. There are 33 questions in this question paper with internal choice.
2. SECTION A consists of 16 multiple-choice questions carrying 1 mark each.
3. SECTION B consists of 5 very short answer questions carrying 2 marks each.
4. SECTION C consists of 7 short answer questions carrying 3 marks each.
5. SECTION D consists of 2 case-based questions carrying 4 marks each.
6. SECTION E consists of 3 long answer questions carrying 5 marks each.
7. All questions are compulsory.
8. The use of log tables and calculators is not allowed
Section A
a) a chemical reaction takes place b) products appear,
c) catalysts are produced. d) reactants disappear
1. Choose the most appropriate answer for the statement, "Rearrangement of atoms occurs whenever a chemical
bond breaks or is formed, when
[1]
a)
1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
 3d
10 b)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
6
 4s
2 
4p
2
c)
1s
2
 2s
2
 2p
6
 3s
2
 3p
5
 4s
1 
3d
9
 4s
2 d)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
8
 4s
2
2. An atom of an element contains 29 electrons and 35 neutrons. The electronic configuration of an element [1]
a) zero b) < 0
c) unity d) different for each element
3. The enthalpies of all elements in their standard states are: [1]
a)
n = 1,2,3..
l= 0,1,..n;
m = -l,-l+1, ..0,1..l-1, l
b)
n = 1,2,3..
l= 0,1,..n-1;
m = 0,1..l-1, l
c)
n = 1,2,3..
l= 0,1,..n
m= -l,-l+1, ..0,1
d)
n = 1, 2, 3..
l = 0, 1,.. n-1;
ml = -l,-l+1, ..0,1..l-1, l
4. According to the quantum theoretical model of an atom, each orbital is designated by three quantum numbers
labelled as n, l, and ml. The values these can take are:
[1]
Page 1 of 13
a) one kg of bonds completely to obtain atoms
in the gas phase.
b) one mole of bonds completely to obtain
atoms in the liquid phase.
c) one kg of bonds completely to obtain atoms
in the liquid phase.
d) one mole of bonds completely to obtain
atoms in the gas phase.
5. Enthalpy of atomization is enthalpy change on breaking: [1]
a) +2, +1, 0, -1, -2 b) s, p, d
c) 0, 1, 2 d) 2l + 1
6. For azimuthal quantum number (l) = 2, the values of magnetic quantum number will be: [1]
a) +4 b) Zero
c) +8 d) -8
7. When methane is burnt in oxygen to produce CO
2
 and H
2
O the oxidation number of carbon changes by? [1]
a) *CH
3 
- CH
2 
- Br b) *CH
3 
- CH
2 
- Cl
c) *CH
3
 - CH
2
 - I d) *CH
3
 - CH
2
 - CH
3
8. In which of the following compounds the carbon marked with asterisk is expected to have greatest partial
positive charge?
[1]
a) b)
c) d)
9. Which of the following compounds is not aromatic? [1]
a) Period 3, group 1 b) Period 4, group 5
c) Period 4, group 6 d) Period 4, group 6
10. Predict the position of an element having the electronic configuration ls 
2
2s
2
2p
6
3s
2
3p
6
3d
5
4s
1
.
[1]
a) mass and its transformations to and from
other forms of energy.
b) heat and its transformations to and from
other forms of energy.
c) kinetic energy and its transformations to and
from other forms of energy.
d) potential and its transformations to and from
other forms of energy.
11. Thermodynamics is the branch of physical science concerned with [1]
a) Nitrobenzene b) Benzene
c) Toluene d) Benzoic Acid
12. Among the following compounds, the one that is most reactive towards electrophilic nitration is ________. [1]
13. Assertion: Cis- 1, 3-dihydroxycyclohexane exists in a boat conformation. 
Reason: In the boat form, there will not be hydrogen bonding between the two hydroxyl groups.
[1]
Page 2 of 13
Section B
Section C
a) If both Assertion & Reason are true and the
reason is the correct explanation of the
assertion.
b) If both Assertion & Reason are true but the
reason is not the correct explanation of the
assertion.
c) If Assertion is true statement but Reason is
false.
d) If both Assertion and Reason are false
statements.
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
14. Assertion (A): Addition of HCl on  is faster than . 
Reason (R): Alkene that can form more stable carbocation they have higher rate of addition with HX.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
15. Assertion (A): Threshold frequency is a characteristic for a metal. 
Reason (R): Threshold frequency is the maximum frequency required for the ejection of electrons from the
metal surface.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
16. Assertion (A): The balancing of chemical equations is based on the law of conservation of mass. 
Reason (R): Total mass of reactants is equal to the total mass of products.
[1]
17. At 500 K, equilibrium constant, K
c
, for the following reaction is 5. 
 
What would be the equilibrium constant K
c
 for the reaction? 
2HI(g)  H
2
(g) + I
2
(g)
[2]
( g ) + ( g ) ? H I ( g ) 1 2 H 2 1 2 I 2 ? 18. The electronic configuration of an element is 1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
. Locate the element in the periodic table.
[2]
19. What will be the mass of one 
12
C atom in g?
[2]
20. Unsaturated compounds undergo addition reactions. Why? [2]
OR
Explain why the system are not aromatic. 
21. Give the number of electrons in the species: , H
2 
and . [2] H + 2 O + 2 22. Arrange the following sets of molecules in the decreasing order of bond angle.
i. SF
6
, CCI
4
, H
2
O, NH
3
ii. CH
4
, NH
3
, H
2
O, BF
3
[3]
Page 3 of 13
Section D
iii. H
2
O, BEH
2
, AICI
3
, BeH
2
 H
2
S
23. Answer: [3]
Two liters of an ideal gas at a pressure of 10 atm expands isothermally at 25 °C into a vacuum until its
total volume is 10 liters. How much heat is absorbed and how much work is done in the expansion?
[1] (i)
What is the enthalpy change for an adiabatic process? [1] (ii)
Predict the sign of S for the following reaction: CaCO
3
(s)  CaO(s) + CO
2
(g)
[1] (iii)
? - ? ? 24. 1 g of graphite is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atmospheric pressure
according to the equation C (graphite) + O2(g)  CO
2
 (g). During the reaction, temperature rises from 298 K
to 299 K. If the heat capacity of the bomb calorimeter is 20.7 kJ / K, what is the enthalpy change for the above
reaction at 298 K and 1 atm?
[3]
? 25. Identify the substances oxidised reduced oxidizing agent and reducing the agent for each of the following
reactions:
i. 2AgBr(s) + C
6
H
6
O
2
(aq)  2Ag(s) + 2HBr(aq) + C
6
H
4
O
2
(aq)
ii. HCHO(l) + 2[Ag(NH
3
)
2
]
+
(aq) + 3OH
-
(aq)  2Ag(s) + HCOO
-
(aq) + 4NH
3
 (aq) + 2H
2
O(l)
iii. HCHO(l) + 2Cu
2+
(aq) + 50H
-
(aq)  Cu
2
O(s) + HCOO
-
(aq) + 3H
2
O(I)
[3]
? ? ? 26. Which of the following sets of orbitals are degenerate and why?
1. 1s, 2s and 3s in Mg atom
2. 2p
x
, 2p
y
 and 2p
z
 in C atom
3. 3s, 3p
x
 and 3d orbitals in H atom
[3]
27. Give the properties of the oxides in a particular period. [3]
28. What is the difference between molality and molarity? [3]
29. Read the text carefully and answer the questions:
IUPAC (International Union of Pure and Applied Chemistry) system of nomenclature. Common names are
useful and in many cases indispensable, particularly when the alternative systematic names are lengthy and
complicated. A systematic name of an organic compound is generally derived by identifying the parent
hydrocarbon and the functional group(s) attached to it. By using prefixes and suffixes, the parent name can be
modified to obtain the actual name. In a branched-chain compound, small chains of carbon atoms are attached at
one or more carbon atoms of the parent chain. The small carbon chains (branches) are called alkyl groups. An
alkyl group is derived from a saturated hydrocarbon by removing a hydrogen atom from carbon. Abbreviations
are used for some alkyl groups. For example, methyl is abbreviated as Me, ethyl as Et, propyl as Pr and butyl as
Bu.
[4]
OR
Draw the structure of 3-Ethyl-4,4-dimethylheptane. (i)
Why CH
4
 after becoming-CH
3
 called a methyl group?
How is the numbering in branched chain hydrocarbon done? (ii)
Derive the structure of 2-Chlorohexane. (iii)
30. Read the text carefully and answer the questions:
Covalent molecules formed by heteroatoms bound to have some ionic character. The ionic character is due to
shifting of the electron pair towards A or B in the molecule AB. Hence, atoms acquire small and equal charge
[4]
Page 4 of 13
Page 5


Time Allowed: 3 hours Maximum Marks: 70 
General Instructions:
1. There are 33 questions in this question paper with internal choice.
2. SECTION A consists of 16 multiple-choice questions carrying 1 mark each.
3. SECTION B consists of 5 very short answer questions carrying 2 marks each.
4. SECTION C consists of 7 short answer questions carrying 3 marks each.
5. SECTION D consists of 2 case-based questions carrying 4 marks each.
6. SECTION E consists of 3 long answer questions carrying 5 marks each.
7. All questions are compulsory.
8. The use of log tables and calculators is not allowed
Section A
a) a chemical reaction takes place b) products appear,
c) catalysts are produced. d) reactants disappear
1. Choose the most appropriate answer for the statement, "Rearrangement of atoms occurs whenever a chemical
bond breaks or is formed, when
[1]
a)
1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
 3d
10 b)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
6
 4s
2 
4p
2
c)
1s
2
 2s
2
 2p
6
 3s
2
 3p
5
 4s
1 
3d
9
 4s
2 d)
1s
2
 2s
2
 2p
6
 3s
2
 3p 4s
2 
3d
8
 4s
2
2. An atom of an element contains 29 electrons and 35 neutrons. The electronic configuration of an element [1]
a) zero b) < 0
c) unity d) different for each element
3. The enthalpies of all elements in their standard states are: [1]
a)
n = 1,2,3..
l= 0,1,..n;
m = -l,-l+1, ..0,1..l-1, l
b)
n = 1,2,3..
l= 0,1,..n-1;
m = 0,1..l-1, l
c)
n = 1,2,3..
l= 0,1,..n
m= -l,-l+1, ..0,1
d)
n = 1, 2, 3..
l = 0, 1,.. n-1;
ml = -l,-l+1, ..0,1..l-1, l
4. According to the quantum theoretical model of an atom, each orbital is designated by three quantum numbers
labelled as n, l, and ml. The values these can take are:
[1]
Page 1 of 13
a) one kg of bonds completely to obtain atoms
in the gas phase.
b) one mole of bonds completely to obtain
atoms in the liquid phase.
c) one kg of bonds completely to obtain atoms
in the liquid phase.
d) one mole of bonds completely to obtain
atoms in the gas phase.
5. Enthalpy of atomization is enthalpy change on breaking: [1]
a) +2, +1, 0, -1, -2 b) s, p, d
c) 0, 1, 2 d) 2l + 1
6. For azimuthal quantum number (l) = 2, the values of magnetic quantum number will be: [1]
a) +4 b) Zero
c) +8 d) -8
7. When methane is burnt in oxygen to produce CO
2
 and H
2
O the oxidation number of carbon changes by? [1]
a) *CH
3 
- CH
2 
- Br b) *CH
3 
- CH
2 
- Cl
c) *CH
3
 - CH
2
 - I d) *CH
3
 - CH
2
 - CH
3
8. In which of the following compounds the carbon marked with asterisk is expected to have greatest partial
positive charge?
[1]
a) b)
c) d)
9. Which of the following compounds is not aromatic? [1]
a) Period 3, group 1 b) Period 4, group 5
c) Period 4, group 6 d) Period 4, group 6
10. Predict the position of an element having the electronic configuration ls 
2
2s
2
2p
6
3s
2
3p
6
3d
5
4s
1
.
[1]
a) mass and its transformations to and from
other forms of energy.
b) heat and its transformations to and from
other forms of energy.
c) kinetic energy and its transformations to and
from other forms of energy.
d) potential and its transformations to and from
other forms of energy.
11. Thermodynamics is the branch of physical science concerned with [1]
a) Nitrobenzene b) Benzene
c) Toluene d) Benzoic Acid
12. Among the following compounds, the one that is most reactive towards electrophilic nitration is ________. [1]
13. Assertion: Cis- 1, 3-dihydroxycyclohexane exists in a boat conformation. 
Reason: In the boat form, there will not be hydrogen bonding between the two hydroxyl groups.
[1]
Page 2 of 13
Section B
Section C
a) If both Assertion & Reason are true and the
reason is the correct explanation of the
assertion.
b) If both Assertion & Reason are true but the
reason is not the correct explanation of the
assertion.
c) If Assertion is true statement but Reason is
false.
d) If both Assertion and Reason are false
statements.
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
14. Assertion (A): Addition of HCl on  is faster than . 
Reason (R): Alkene that can form more stable carbocation they have higher rate of addition with HX.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
15. Assertion (A): Threshold frequency is a characteristic for a metal. 
Reason (R): Threshold frequency is the maximum frequency required for the ejection of electrons from the
metal surface.
[1]
a) Both A and R are true and R is the correct
explanation of A.
b) Both A and R are true but R is not the
correct explanation of A.
c) A is true but R is false. d) A is false but R is true.
16. Assertion (A): The balancing of chemical equations is based on the law of conservation of mass. 
Reason (R): Total mass of reactants is equal to the total mass of products.
[1]
17. At 500 K, equilibrium constant, K
c
, for the following reaction is 5. 
 
What would be the equilibrium constant K
c
 for the reaction? 
2HI(g)  H
2
(g) + I
2
(g)
[2]
( g ) + ( g ) ? H I ( g ) 1 2 H 2 1 2 I 2 ? 18. The electronic configuration of an element is 1s
2
 2s
2
 2p
6
 3s
2
 3p
6
 4s
1
. Locate the element in the periodic table.
[2]
19. What will be the mass of one 
12
C atom in g?
[2]
20. Unsaturated compounds undergo addition reactions. Why? [2]
OR
Explain why the system are not aromatic. 
21. Give the number of electrons in the species: , H
2 
and . [2] H + 2 O + 2 22. Arrange the following sets of molecules in the decreasing order of bond angle.
i. SF
6
, CCI
4
, H
2
O, NH
3
ii. CH
4
, NH
3
, H
2
O, BF
3
[3]
Page 3 of 13
Section D
iii. H
2
O, BEH
2
, AICI
3
, BeH
2
 H
2
S
23. Answer: [3]
Two liters of an ideal gas at a pressure of 10 atm expands isothermally at 25 °C into a vacuum until its
total volume is 10 liters. How much heat is absorbed and how much work is done in the expansion?
[1] (i)
What is the enthalpy change for an adiabatic process? [1] (ii)
Predict the sign of S for the following reaction: CaCO
3
(s)  CaO(s) + CO
2
(g)
[1] (iii)
? - ? ? 24. 1 g of graphite is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atmospheric pressure
according to the equation C (graphite) + O2(g)  CO
2
 (g). During the reaction, temperature rises from 298 K
to 299 K. If the heat capacity of the bomb calorimeter is 20.7 kJ / K, what is the enthalpy change for the above
reaction at 298 K and 1 atm?
[3]
? 25. Identify the substances oxidised reduced oxidizing agent and reducing the agent for each of the following
reactions:
i. 2AgBr(s) + C
6
H
6
O
2
(aq)  2Ag(s) + 2HBr(aq) + C
6
H
4
O
2
(aq)
ii. HCHO(l) + 2[Ag(NH
3
)
2
]
+
(aq) + 3OH
-
(aq)  2Ag(s) + HCOO
-
(aq) + 4NH
3
 (aq) + 2H
2
O(l)
iii. HCHO(l) + 2Cu
2+
(aq) + 50H
-
(aq)  Cu
2
O(s) + HCOO
-
(aq) + 3H
2
O(I)
[3]
? ? ? 26. Which of the following sets of orbitals are degenerate and why?
1. 1s, 2s and 3s in Mg atom
2. 2p
x
, 2p
y
 and 2p
z
 in C atom
3. 3s, 3p
x
 and 3d orbitals in H atom
[3]
27. Give the properties of the oxides in a particular period. [3]
28. What is the difference between molality and molarity? [3]
29. Read the text carefully and answer the questions:
IUPAC (International Union of Pure and Applied Chemistry) system of nomenclature. Common names are
useful and in many cases indispensable, particularly when the alternative systematic names are lengthy and
complicated. A systematic name of an organic compound is generally derived by identifying the parent
hydrocarbon and the functional group(s) attached to it. By using prefixes and suffixes, the parent name can be
modified to obtain the actual name. In a branched-chain compound, small chains of carbon atoms are attached at
one or more carbon atoms of the parent chain. The small carbon chains (branches) are called alkyl groups. An
alkyl group is derived from a saturated hydrocarbon by removing a hydrogen atom from carbon. Abbreviations
are used for some alkyl groups. For example, methyl is abbreviated as Me, ethyl as Et, propyl as Pr and butyl as
Bu.
[4]
OR
Draw the structure of 3-Ethyl-4,4-dimethylheptane. (i)
Why CH
4
 after becoming-CH
3
 called a methyl group?
How is the numbering in branched chain hydrocarbon done? (ii)
Derive the structure of 2-Chlorohexane. (iii)
30. Read the text carefully and answer the questions:
Covalent molecules formed by heteroatoms bound to have some ionic character. The ionic character is due to
shifting of the electron pair towards A or B in the molecule AB. Hence, atoms acquire small and equal charge
[4]
Page 4 of 13
Section E
but opposite in sign. Such a bond which has some ionic character is described as a polar covalent bond. Polar
covalent molecules can exhibit a dipole moment. The dipole moment is equal to the product of charge
separation, q and the bond length, d for the bond. The unit of dipole moment is Debye. One Debye is equal to
10
-18
 esu cm. 
The dipole moment is a vector quantity. It has both magnitude and direction. Hence, the dipole moment of
molecules depends upon the relative orientation of the bond dipole, but not the polarity of bonds alone. The
symmetrical structure shows a zero dipole moment. Thus, a dipole moment help to predict the geometry of the
molecules. Dipole moment values can be used to distinguish between cis- and trans-isomers; ortho-, meta- and
para-forms of a substance, etc. The percentage of ionic character of a bond can be calculated by the application
of the following formula: 
% ionic character = 
OR
× 1 0 0 E x p e r i m e n t a l v a l u e d i p o l e m o m e n t T h e o r e t i c a l v a l u e o f d i p o l e m o m e n t Out of  and  which compounds have zero dipole moments?
(i)
A diatomic molecule has a dipole moment of 1.2D. If the bond length is 1.0  10
-8
cm, what fraction of
charge does exist on each atom?
(ii)
× The dipole moment of NF
3 
is very much less that of NH
3
. Why? (iii)
A covalent molecule, x-y, is found to have a dipole moment of 1.5  10
-29
 cm and a bond length 150 pm.
What will be the percentage of ionic character of the bond?
× 31. Attempt any five of the following: [5]
What is Huckel rule? [1] (i)
How is alkene produced by vicinal dihalide? [1] (ii)
Write the general formula for alkynes. [1] (iii)
Suggest the name of a Lewis acid other than anhydrous aluminium chloride which can be used during
ethylation of benzene.
[1] (iv)
Classify the hydrocarbons according to the carbon-carbon bond. [1] (v)
What are benzenoids? [1] (vi)
Write IUPAC name: [1] (vii) C - C H = C H - C - C H = C H - H - C - C H = C H 3 H 2 C | C 2 H 5 H 2 H 2 32. The pH of milk, black coffee, tomato juice, lemon juice, and egg white are 6.8, 5.0, 4.2, 2.2 and 7.8 respectively.
Calculate corresponding hydrogen ion concentration in each.
[5]
OR
Describe the effect of:
a. addition of H
2
b. addition of CH
3
OH
c. removal of CO
d. removal of CH
3
OH
On the equilibrium of the reaction: 2H
2
(g) + CO(g)  CH
3
OH(g) ? 33. Answer: [5]
Page 5 of 13