F.Sc. Part 1 Chemistry.Ch.07.Test (Malik Xufyan)

th
Maliks Chemistry -9 Class
(Board Paper-wise Test Series)
th
(Board Paper -wise Test Series)
Maliks Chemistry - F.Sc. l
Maliks Chemistry- F.Sc. ll
5
6
7
8
th
(Chapter-wise Test Series)
th
Maliks Chemistry - F.Sc. l
Maliks Chemistry- F.Sc. ll
1
2
3
4
Msc.Chemistry
CHEMISTRYCHEMISTRYCHEMISTRY
Chapter-wise
Test Series
Malik Xufyan
JIAS ACADEMY
Malik
Jhang Ins tute for Advanced Studies
0313-7355727
Our Other Publica ons
Jhang Ins tuteJhang Ins tuteJhang Ins tute
for Advance Studies
Jhang Sadar

CHEMISTRYCHEMISTRYCHEMISTRYCHEMISTRYCHEMISTRYCHEMISTRY
Malik Xufyan
JIAS ACADEMY
Malik
‫ﺧﻮﺷﺨﺒﺮی‬
Jhang Ins tute for Advanced Studies
Contact:
0313-7355727

Chapter # Topic Page #
Basic concepts – Unsolved paper1
2
3
4
5
6
7
8
9
10
11
5
6
16
17
24
25
36
37
45
46
54
55
64
65
73
74
83
84
93
94
103
104
Experimental Techniques – Solved Paper
Gases – Unsolved Paper
Gases – Solved Paper
Liquid – Unsolved Paper
Liquid – Solved Paper
Atomic Structure – Unsolved Paper
Atomic Structure – Solved Paper
Chemical Bonding –Unsolved Paper
Chemical Bonding – Solved Paper
Thermochemistry – Unsolved Paper
Thermochemistry – Solved Paper
Chemical Equilibrium – Unsolved Paper
Chemical Equilibrium – Solved Paper
Solu on – Unsolved Paper
Solu on – Solved Paper
Electrochemistry – Unsolved Paper
Electrochemistry – Solved Paper
Chemical Kine cs – Unsolved Paper
Chemical Kine cs – Solved Paper
Basic concepts – Solved Paper
Experimental techniques – Unsolved Paper
INDEX

Chapter#7: Thermochemistry Malik Chemistry
Jhang Institute for Advanced65
Name : CH # Thermochemistry Class 11th
Chemistry Test # 07, CH # 07 (Complete) Marks : 85
Time : 2 & Half Hour Objective & Subjective JIAS Test System
Section;I: Objective
1. Choose the correct answer. 17x1=17
Sr # Statement A B C D
1. The branch of chemistry which deals with the
thermal energy changes in a chemical reaction
is called
Thermochemistry Electrochemistry Thermodynamics Photochemistry
2. A stable system has ……. energy as possible Highest Lowest Intermediate May have any
amount of energy
3. Negative enthalpy change of a chemical
reaction does not mean that a reaction is
Spontaneous Non spontaneous Positive Negative
4. Hess’s law is analogous to Law of transformation Law of heat exchange Law of heat
summation
Law of
composition
5. Which one of the following cannot be
measured by Hess’s law?
Heat of combustion Enthalpy change Internal energy Heat of
formation
6 A calorimeter is an instrument used for the
measurement of
Heat of reaction Heat of combustion Heat of formation Heat of
vapourization
7. In a bomb calorimeter the, heat of the reaction
is measured at
Constant volume Constant pressure Both of them None of them
8. Water flows from higher level to the lower
level
Spontaneous process Non spontaneous
process
Endothermic process Exothermic
process
9. Internal energy of a substance is equal to K.E of all of its
molecules
P.E of all of its
molecules
Sum of both
energies
Heat energy
10. Born –Haber cycle is used to determine the Combustion energy Lattice energy Decomposition
energy
Formation energy
11. If an endothermic reaction is allowed to
take place very rapidly in the air ,then the
temperature of the surrounding air
Remain constant Decreases Increases Unchanged
12. The enthalpy change when one mole of a
substance is completely burnt in excess of
oxygen is called
Enthalpy of atomization Enthalpy of
neutralization
Enthalpy of
formation
Enthalpy of
combustion
13. Kinetic energy of the molecules of a gaseous
substance is due to
Translational motion Vibrational motion Rotational motion Sum of all
possible motions
14. Which one of the following have maximum
energy
Reactions Products Trasition state Catalyst
15. For an endothermic reaction ,enthalpy of the
reactants
Is smaller than that of
products
Is greater than that of
products
May be any Is equal to
product
16. When no work is done by the system ,the
volume of the system
Increase Decrease Remain constant Fluctuate
17. Anything under examination in the laboratory
is called
Electrolyte Reactant System Substance

Jhang Institute for Advanced Studeies 66
Section-Il: Short questions
2.Attempt only EIGHT questions. 8 x 2= 16
i. Do we determine the ∆H in the laboratory for fuel, food
etc?
ii. How temperature is a state function but heat is not .Why?
iii. What is lattice energy? Give example
iv. What is meant by standard enthalpy of atomization?
v. Differentiate between spontaneous and non-spontaneous
process?
vi. Differentiate between path function and state function.
vii. Is it essential that spontaneous reaction should be exo-
thermic? Comment on it.
viii.Enthalpy of neutralization of any strong acid with strong
base is same. Explain.
ix. Why it is necessary to mention physical states of reactants
and products in thermodynamic equations?
x. What is Born Haber cycle? Give its uses.
xi. Give the significance of Lattice energy.
xii. Define enthalpy of combustion with example.
3. Attempt only 8 questions 8 X 2 = 16
i. Differentiate between exothermic and endothermic reac-
tions?
ii. For what purpose bomb calorimeter is used?
iii. Define enthalpy of formation and enthalpy of reaction
with examples.
iv. What is first law of thermodynamics?
v. Specific heat of a substance depends upon the nature of
substances. Comment?
vi. State Hess’s law of constant heat of summation?
vii. Differentiate between temperature and heat?
viii. Define enthalpy of neutralization with example.
ix. Define surrounding and system?
x. Define the term enthalpy?
xi. Why the total energy the products are never equal to that
of reactants?
4. Attempt any 6 questions 6 x 2 =12
i. What are the ways to transfer energy to and from the sys-
tem?
ii. What is internal energy?
iii. Draw a diagram of bomb calorimeter.
iv. What is the construction of glass calorimeter?
v. Why enthalpy of reaction of some compounds cannot be
measured directly?
vi. What is thermochemical equation giving at least three ex-
amples?
vii. Justify that the heat of formation of compound is the sum
of all the other enthalpies.
viii. What is heat of solution? Give example.
ix. Draw a comprehensive diagram showing enthalpy of re-
action.
Section-ll: Long Questions. 8 x 3 = 24
Attempt any 3 questions.
5) a) Write a detailed note on bomb calorimeter with exam-
ple.
(b) Define and explain Hess’s law of constant heat
summation. Explain with examples and give its
application.
6) a) Write detailed note on Born –Haber cycle calculate the
lattice energy of sodium by drawing a cyclic diagrammat-
ic elaboration?
(b) What is the meaning of the term enthalpy of
ionization? If the heat of neutralization of HCl and
NaOH is -57.3kj/mol and heat of neutralization
of CH3
COOH with NaOH is -55.2 kJ/mol. Cal-
culate the enthalpy of ionization of CH3
COOH?
7) How would you explain that work is the product of pres-
sure and volume in a thermodynamic system?
(b) Prove that the change in internal energy of a
system at constant volume is equal to heat absorbed
by the system?
8) (a) What do you know about first law of thermodynamics
with the help of enthalpy?
b) Write note glass calorimeter, working and calcu-
lation.
9) (a) Burning of candle is spontaneous process. Explain.
(b) What are spontaneous and non-spontaneous re-
actions? Give examples.

Section-l: Short questions
2. Attempt only EIGHT questions 8 x 2= 16
i. Can we determine the ∆H in the laboratory for fuel, food etc?
Yes, we can determine ∆H in the laboratory for fuel, food with the help of bomb calorimeter. A bomb
calorimeter is usually used for the accurate determination of the enthalpy of combustion for food, fuel
and other compounds.
We help for this, use formula: q = c x ∆T
ii. How Temperature is a state function but heat is not .why?
Temperature is property of system which has some definite values for initial and final states, and which
is independent to bring about change.
∆T= Final temperature – initial temperature
∆T= T2
- T1
While heat has not define initial and final conditions or state that’s why heat is path function not state
function.
iii. What is lattice energy? Give example.
Ans: Lattice energy: The lattice energy of an ionic crystal is the enthalpy of formation of one mole of
the ionic compound from gaseous ions under standard conditions.
Example: Na+
(g)
+ Cl-
Na+
Cl-
∆Ho
latt
= -787 kJ mol-
iv. What is meant by standard enthalpy of atomization?
Ans: Standard enthalpy of atomization:
The enthalpy change when one mole of gaseous atoms are formed from the elements under the stan-
dard conditions is called enthalpy of atomization.
Examples:
½ H(g)
H ∆H = 218 kJ/mole
Cl2
Cl(g)
∆H = + 121 kJ/mole
v. Differentiate between spontaneous and non-spontaneous process?
Ans:
Sr # Spontaneous process Non-spontaneous process
1. The process which takes place on its own
without any outside help and moves from a
non–equilibrium state to equilibrium state is
called spontaneous or natural process.
The process which does not take place on its
own and does not occur in nature is called as
non–spontaneous
2. It is real, unidirectional and irreversible It is reverse of the spontaneous process
3. water flows from higher level to low level Pumping of water uphill
4. Flow of heat from hot to colder region It flow of heat from colder to hotter region
vi. Differentiate between path function and state function?
Ans:
Sr # State Function Path Function
1. A macroscopic property of a system
which has some definite value for initial
and final state and independent of the path
A macroscopic property of a system which has not
some definite value for initial and final state and
dependent of the path
2. (i) Pressure (ii) Temperature
(iii) Internal energy are state function
Heat, work and enthalpy are path function.
3. It has initial and final conditions It has not initial and final state.
vii. Is it essential that spontaneous reaction should be exothermic? Comment on it.

Our common experience, shows hat spontaneous process proceed with a decrease in energy, we might
expect, therefore, that a chemical reaction would proceed spontaneously if the reaction system de-
crease in energy by transferring heat to its surroundings. In other words, we might expect all exother-
mic reaction spontaneous; this is usually true but not always. There are many endothermic changes
that proceed spontaneously although they absorb heat. For example:
H2
O H2
O ∆H = 44.0 kJ/mole
NH4
Cl NH4+
(aq)
+ Cl-
∆H = 15.1 kJ/mole
Thus energy change alone cannot help us to predict, whether a reaction will occur spontaneously or
not.
viii. Enthalpy of neutralization of any strong acid with strong base is same. Explain.
Ans: Enthalpy of neutralization of sodium hydroxide by hydrochloric acid is -57.4 kJmol-
. Note that a
strong acid HCl and a strong base, NaOH ionize completely in dilute solutions as follows. Note that a
strong acid (HCl) and a strongbase (NaOH) ionize completely in dilute solutions as follows
HCl (aq)
H+
(aq)
+ Cl-
(aq)
NaOH (aq)
Na+
(aq)
+ OH-
(aq)
With these solutions are mixed together during the process of neutralization, the only change that
actually occurs is the formation of water molecules leaving the sodium ions and the chloride ions as
free ions in solution. Thus the enthalpy of neutralization is merely the heat of formation of one mole of
liquid water from its ionic components,
H+
(aq)
+ Cl-
(aq) + Na+
(aq)
+ OH-
(aq)
Cl-
(aq)
+ Na+
(aq)
H+
+ OH-
(aq)
H2
O ∆H= -57.4 kJmol-
Enthalpy of neutralization of any strong acid with strong base is approximately the
same -57.4 kJmol-1
ix. Why it is necessary to mention physical states of reactants and products in thermodynamic equa-
tions?
Ans: The heat of reaction depends upon the physical states of the reactants and products, heat of reaction
is different in different physical states therefore, while writing a thermochemical equation it is essential
to mention the physical states of the reactants and products.e.g
H2(g)
+ ½ O2(g)
H2
O(g)
∆H = -241.5 KJ mol-1
H2(g)
+ ½ O2(g)
H2
O(l)
∆ H = -285.8 KJ mol-1
x. What is Born Haber cycle? Give its uses.
Ans: Born Haber cycle:
This cycle has wide applications. It finds its special applications in Hess’s law. It states that energy
change in a cyclic process is always zero. It enables us, to calculate the lattice energies of binary com-
pounds such as M+
X-
.
Uses:
• The lattice energy gives us some idea of the force of attraction between Na+
and Cl-
ions in crystalline
sodium chloride.
• Lattice energies are very helpful in discussing the structure, bonding and properties of ionic com-
pounds.
xi. Give significance of lattice energy.
Ans: Significance of lattice energy:
• The lattice energy gives us some idea of the force of attraction between Na+
and Cl-
ions in crystalline
sodium chloride.
• Lattice energies are very helpful in discussing the structure, bonding and properties of ionic com-
pounds.
xii. Define enthalpy of combustion with example.

Ans:Standard Enthalpy of Combustion:
The enthalpy change when one mole of a substance is completely burnt in excess of oxygen under stan-
dard conditions.
Examples:
C2
H5
OH(l)
+ 3O2(g)
2CO2(g)
+ 3H2
O(l)
∆H = – 1368 kJ/m
C(s)
+ O2(g)
CO2(g)
∆H = – 393.7 kJ/m
2Al(s)
+ O2(g)
Al2
O3(s)
∆H = – 1675.7 kJ/m
3. Attempt only 8 questions 8 X 2 = 16
i. Differentiate between exothermic and endothermic reactions.
Sr # Exothermic reactions Endothermic reactions
1. Those thermochemical reactions in which
heat is evolved as a result of reaction are
called as exothermic reactions
Those thermochemical reactions in which heat
is absorbed as a result of reaction are called as
endothermic reaction.
2. C(s)
+ O2(g)
CO2(g)
∆H = – 393.7 kJ/mole
N2(g)
+ O2(g)
2NO(g)
∆H =+180.51kJ/mole
3. H2(g)
+ O2(g)
H2
O(l)
∆H = – 285.5 kJ/mole
H2
O(l)
H2(g)
+ O2(g)
∆H = + 285.58 kJ/mole
4. N2
+ 3H2(g)
2NH3(g)
∆H = – 41.6 kJ/mole
H2(g)
+ I2(g)
2H I
∆H = + 52.96 kJ/mole
ii. For what purpose bomb calorimeter is used?
Ans:A bomb calorimeter is usually used for the accurate determination of the enthalpy of combustion for
food, fuel and other compounds.
We help for this, use formula:
q = c x ∆T
iii. Define enthalpy of formation and enthalpy of reaction with examples.
Ans: Standard Enthalpy of reaction:
The enthalpy change when no. of moles of reactants as indicated by the balanced chemical equation
react completely together to give the products under the standard conditions.
Examples:
H2(g)
+ O2(g)
H2
O(l)
∆H = – 285.5 kJ/m
N2(g)
+ O2(g)
2NO(g)
∆H = + 180.5 kJ/m
iv. What is first law of thermodynamics?
Ans: First law of thermodynamics:
1. The first law of the thermodynamics, also called the law of conservation of energy, states that energy
can neither be created nor destroyed but can be changed from one form to another. or
2. In other words, a system cannot destroy, or created energy. However, it can exchange energy with its
surrounding in the form of heat and work.
v. Specific heat of a substance depends upon the nature of substances. Comment?
Ans:Heat capacity (C) does change with mass. However, specific heat is the heat capacity per unit mass
(c = C/m).
Therefore if you double the amount of mass in your system, you’ve doubled its heat capacity, but you’ve
kept the specific heat the same.
vi. State Hess’s law of constant heat of summation?
Ans: Hess’s law: This law states that:
If a chemical changes takes place by several different routes, the overall energy change is the same,

regardless of the route by which the chemical occurs, provided the initial and final conditions are the
same.
Mathematically: ∑∆ H (cycle) = 0
vii. Differentiate between temperature and heat?
Ans:
Sr # Heat Temperature
1. The measure of total energy of a substance
is called heat.
It is measure of average K.E of the molecules
in the system.
2. It is denoted by ‘q’. It is denoted by ‘T’
3. It depends upon the quantity of a substance It is independent of the quantity of a substance
4. It is measured by calorimeter It is measured by thermometer
5. It is not a state function. It is a state function.
6. Relationship is q= m x S x ∆T
viii. Define enthalpy of neutralization with example.
Ans: Enthalpy of neutralization:
It is the amount of heat evolved or absorbed when one mole of H+
ions from an acid reacts with one
mole of OH-
from a base to form one mole of H2
O. Under standard conditions it is called standard
enthalpy of neutralization and it is denoted by ∆Hn
.
Example:
H+
+ OH-
H2
O ∆Hn
= -57.4 KJ mol-1
ix. Define surrounding and system?
Ans:System:The substance which is under experiment or under observation is called as system.
Examples:
1. Pb(NO3
)2
in decomposition of Pb(NO3
)2
.
2. Zn and CuSO4
solution, the reaction mixture in the vessel.
3. CaCO3
in thermal decomposition of CaCO3
Surroundings:Everything around the system which is not a part of system is called surroundings.
Example:During the reaction between Zn and CuSO4
solution vessel and air etc are surroundings
x. Define the term enthalpy?
Ans: Enthalpy:
The total heat contents of a system. It is denoted by H
It is not state function of system
Formula: H = E + PV
xi. Why the total energy the products are never equal to that of reactants?
Ans: Substances exist, because they possess energy. Difference substances have different amounts of en-
ergy associated with them. Due to this reason, the total energy of the products is never equal to those
reactants.
4. Attempt any 6 questions. 6 x 2 =12
i. What are the ways to transfer energy to and from the system?
Ans: There are two fundamental ways for transferring energy to or from system. These ways are heat and
work.
ii. What is internal energy?

Ans: The total of all kinds of K.E and P.E of all the particles of a system is called as internal energy
It is denoted by “E’
It is a sate function of system
Formula: E = K.E + P.E
iii. Draw a diagram of bomb calorimeter.
Ans:
iv. What is the construction of glass calorimeter?
Ans:
Beakers, cotton wool, stirrer, thermometer, HCl + NaOH, Lid with figure
v. Why enthalpy of reaction of some compounds cannot be measured directly?
Ans:There are many compounds for which ∆H cannot be measured diectl by calorimetric method. The
reason is that some compounds like tetrachloromethane (CCl4
), cannot be prepared directly by com-
bining carbon and chlorine. Similarly, it does not decompose easily into its constitutent elements. In
the same way, boron oxide (B2
O3
) and aluminium oxide (Al2
O3
) provide problems for the measure-
ment of standard enthalpies of their formation. In these cases, it is difficult to burn these elements in
oxygen, because a protective layer of oxides covers the surface of un-reacted element. Similarly, heat of
formation of CO cannot be measured directly due to the formation of CO2
with it.
vi. What is a thermochemical equation giving at least three examples?
Ans: Thermochemical equation:
“A chemical equation which gives an idea about the heat evolved or absorbed during the reaction is
called a thermochemical equation.”
Examples:
C(s)
+ O2 (g)
CO3(g)
∆H = -393.7 kJ mol-1
H2(g )
+ O2 (g)
H2
O(l)
∆ H = -285.58 kJ mol-1
N2(s)
+ O2 (g)
2NO(g)
∆H = +180.51kJ mol-1
N2(s)
+ 3H2 (g)
2NH3(g)
∆ H = -41.6 kJ mol-1
vii. Justify that the heat of formation of compound is the sum of all the other enthalpies.

Ans:Enthalpy of formation of a compound is equal to the sum of its enthalpy of combustion and enthal-
pies of combustion of elements from which it is formed.
For example: formation of ethyl alcohol.
viii. What is heat of solution? Give example.
Heat of solution:
The standard enthalpy of a solution is the amount of heat absorbed or evolved when one mole of a
substance is dissolved in so much solvent that further dilution in no detectable heat change.
Example:
For example, enthalpy of solution of ammonium chloride is +16.2 KJ mol-
and that of sodium carbon-
ate is -25.0 KJmol-
. In the first case, heat absorbed from the surroundings is indicated by cooling of
solvent (water), an endothermic process. While in the second case, the temperature of the solvent rises
showing that process is exothermic.
ix. Draw a comprehensive diagram showing enthalpy of reaction.
x. Differentiate between enthalpy and internal energy.
Ans:
Sr # Enthalpy Internal energy
1. The total heat contents of a system The total of all kinds of K.E and P.E of all the
particles of a system is called as internal energy
2. It is denoted by H It is denoted by “E’
3. It is not state function of system It is a sate function of system
4. H = E + PV E= K.E + P.E
Section-ll: Long Questions.
Attempt any THREE questions. 8 x 3 = 24
5) a) Write a detailed note on bomb calorimeter with example.
(b) Define and explain Hess’s law of constant heat summation. Explain with examples and give its application.
6) a) Write detailed note on Born –Haber cycle calculate the lattice energy of sodium by drawing a cyclic
diagrammatic elaboration?
b) What is the meaning of the term enthalpy of ionization ?if the heat of neutralization of HCl and NaOH
is -57.3 kj/mol and heat of neutralization of CH3
COOH with NaOH is
-55.2 kJ/mol. Calculate the enthalpy of ionization of CH3
COOH?
7) How would you explain that work is the product of pressure and volume in a thermodynamic system?
b) Prove that the change in internal energy of a system at constant volume is equal to heat absorbed by the
system?
8) (a) What do you know about first law of thermodynamics with the help of enthalpy?
(b) Write note glass calorimeter, working and calculation.
9) (a) Burning of candle is spontaneous process. Explain.
(b) What are spontaneous and non-spontaneous reactions? Give examples.

F.Sc. Part 1 Chemistry.Ch.07.Test (Malik Xufyan)

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to F.Sc. Part 1 Chemistry.Ch.07.Test (Malik Xufyan)

Similar to F.Sc. Part 1 Chemistry.Ch.07.Test (Malik Xufyan) (20)

More from Malik Xufyan

More from Malik Xufyan (20)

Recently uploaded

Recently uploaded (20)

F.Sc. Part 1 Chemistry.Ch.07.Test (Malik Xufyan)