Home/ECAT/ECAT Chemistry Thermochemistry Online Test

ECAT Chemistry Thermochemistry Online Test

Maan AliLast Updated: April 19, 2025

Chemistry Thermochemistry MCQS Online Test

ECAT Chemistry Thermochemistry Chapter Online Test

Total Questions:	108
Time Allowed:	60 Minutes
Total Marks:	108
How to Attempt Test:	Please choose the right Option in MCQ-type question.
Test Helpful For:	ECAT Entry Test Chemistry Online Test Interview Questions about Chemisttry All Universities Entrance Test Recruitments Tests

ECAT Chemistry Thermochemistry Test

Please wait...

Page 1 of 5

Chemistry

1. For a melting of a solid at 25°C, the fusion process requires energy equivalent to 2906 Joules to be added to system considering the process to be reversible at fusion point, the entropy change of the process is

11.272 JK¯¹

2.33 JK¯¹

Insufficient data

9.75 JK¯¹

2. The branch of chemistry which deals with thermal energy change in chemical reaction is called

Thermodynamics

Thermochemistry

Mechanics

Chemical kinetics

3. When water is added to quick lime, the reaction is

Photochemical

Exothermic

Endothermic

Explosive

4. Reaction in which heat is evolved

Non-spontaneous

Endothermic

Spontaneous

Exothermic

5. Endothermic changes are indicated through

Burning of carbon

Making of chemical bond

Breaking of chemical bonds

All of these

6. A spontaneous change means

An increase in internal energy

A lowering of energy

No energy change

A lowering of free energy

7. If an endothermic reaction is allowed to take place very rapidly in the air, the temperature of the surrounding air

Remains constant

Increases

Decreases

Remains same

8. When enthalpy of reactants is higher than products, then reaction will be

Non-spontaneous

Endothermic

Exothermic

Spontaneous

9. Most of the reactions which give stable products are

Exothermic

None of these

Isothermal

Endothermic

10. What type of reaction releases energy and does not require initial energy to occur?

Decomposition

Endothermic

Exothermic

Both a and b

11. When enthalpy of reactants is higher than product then reaction will be

Exothermic

Non-spontaneous

Spontaneous

Endothermic

12. The apparatus used to measure the enthalpy of combustion of a substance is

All above

Bomb calorimeter

Copper calorimeter

Glass calorimeter

13. Heat exchanged in a chemical reaction at constant temperature and pressure is called

Enthalpy change

Free energy change

Internal energy change

Entropy change

14. Which law among the following has same net change whether it takes place directly or indirectly?

Henry’s law

Boyle’s law

Hess’s law

Graham’s law

15. What would be the heat released when an aqueous solution containing 0.5 mole of HNO₃ is mixed with 0.3 mol of OH¯ (enthalpy of neutralization is -57.1 kJ)

28.5 kJ

1.7 kJ

45.7 kJ

17.1kJ

16. A macroscopic property of a system which describes the initial and final state of the system is called

Physical property

Energy of the system

State function

Chemical property

17. In measurement of melting point of solid, the leaker used will be

System

Phase

State

Surrounding

18. Form the above data, the standard heat of formation of KOH in kcal mol¯¹ is

– 68 – 48 + 14

68 + 48 + 14

68 – 48 + 14

– 68 + 48 – 14

19. A chemist heated a balloon by supplying 600 J of heat. The balloon expands doing 200 J of work against the atmospheric pressure. The change in internal energy of

-400J

= - k719

= + k319

0 J

20. The enthalpies of combustion of carbon and carbon monoxide are -390 kJ mol¯¹ and -278 kJ mol¯¹ respectively. The enthalpy of formation of carbon monoxide is

668 kJ mol¯¹

112 kJ mol¯¹

-112 kJ mol¯¹

-668 kJ mol¯¹

21. Sublimation, vaporization, melting and p photosynthesis all are examples of

Chemical process

Physical process

Biochemical process

Endothermic process

22. Two fundamental ways to transfer energy are

Heat and volume

Pressure and temperature

Heat and work

Pressure and volume

23. Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are -382.64kJ mol¯¹ and -145.6kJ¯¹ mol¯¹ respectively. Standard Gibbs energy change for the same reaction at 298 K is

-339.3 kJ mol¯¹

-221.1 kJ mol¯¹

-523.3 kJ mol¯¹

-439.3 kJ mol¯¹

24. In order to decompose 9 g of water 142.5 kJ of heat is required. Hence enthalpy of formation of water is

+285 kJ

-285 kJ

-142.5 kJ

+142.5 kJ

25. For a reaction to occur spontaneously

∆ H must be unity

∆ H must be zero

∆ H must be positive

∆ H must be negative

Page 2 of 5

26. An endothermic reaction is one in which

Heat is absorbed

Heat is converted into electricity

Heat is converted into mechanical work

Heat is evolved

27. The amount of heat which is involved during the completion of a chemical reaction at 25°C and 1 atmospheric pressure is called

Hat of formation

Enthalpy of reaction

Heat of neutralization

Heat of combustion

28. The enthalpies of combustion of carbon and carbon monoxide are -383.5 and -283 kJ mol¯¹ respectively. The enthalpy of formation of carbon monoxide per mole is

110.5 kJ

676.5 kJ

-110.5 kJ

-676.5 kJ

29. For the reaction NaOH + HCl → NaCl + H₂O the change in enthalpy is called

Heat of reaction

Heat of neutralization

Heat of sublimation

Heat of combustion

30. When 50 cm³ of 0.2 n H₂SO₄ is mixed with 50 cm³ of 1 N KOH, the heat liberated is

57.3 kJ

11.46 kJ

573 J

573 kJ

31. Which of the following statement is contrary to first law of thermodynamics?

One form of energy can be transferred to an equivalent amount of the kind of energy

An equivalent amount of heat energy can neither be created nor destroyed

Continuous production of mechanical work without supplying an equivalent amount of heat energy

Work done is independent of its path

32. When a bond breaks

Heat is evolved

No change in heat contents takes place

Heat is absorbed

Temperature increases

33. Which of the following unit represent the largest amount of energy?

Joule

Erg

Calorie

Electron – volt

34. All the naturally occurring processes proceed spontaneously in a direction which lead to

Decrease of free energy

Increase of enthalpy

Increase of free energy

Decrease of entropy

35. The energy required to break 1 mole of bonds to form neutral atom is

Bond length

Bond strength

None of these

Bond energy

36. The bond dissociation energies of H₂, CL₂ and HCl are 104, 58 and 103 kcal respectively. The enthalpy of formation of HCl gas will be

-44 kcal

-11 kcal

-88 kcal

-22 kcal

37. A material or a collection of materials which is under study is called

State function

System

Any substance

Surrounding

38. An adiabatic expansion of an ideal gas always has

Q = 0

W = 0

Decrease in temperature

∆H = 0

39. Most of the thermodynamic parameters are

System

State function

Phase

Surrounding

40. The ∆H values for reaction C + ½ O₂ → CO and CO + ½ O₂ → CO₂ are 100 and 200 kJ respectively. The heat of reaction for C + O₂ → CO₂ will be

50 kJ

300 kJ

100 kJ

150 kJ

41. Two fundamental ways to transfer energy are

Heat and work

Pressure and temperature

Pressure and volume

Heat and volume

42. Total energy of a system is

P.E. + heat energy

P.E, + mechanical energy

P.E, + K.E.

K.E, + heat energy

43. Unit of heat is SI system is

Cal

KCaL

44. Burning of coal in air is initiated by a spark and it is an example of spontaneous reaction because

None of these

Burning of coal is and endothermic process

Coal and air react giving a reversible reaction

Burning of coal in air releases large amount of energy

45. Which of the following units represents largest amount of energy?

Calorie

Joule

Erg

Electron vol

46. One mole of an ideal gas expands isothermally to ten times its original volume. The change in entropy is

2.303 R

10.0 R

0.1 R

100.0 R

47. Which type of reactions cannot occur spontaneously?

Both a and b

Exothermic

Endothermic

Neither

48. Quantity of heat evolved or absorbed during reaction measure according to

∆E = q + w

Q = m x X x ∆ T

∆H = ∆E + P∆V

P∆V + nRT

49. If internal energy of the system is increased

All

Change in state of the system is increased

Chemical reaction may take place

Temperature of the system may rise

50. If at 298 K the bond energies of C-H, C-C, C=C and H-H bonds are respectively 414, 347, 615 and 435 kJ mol¯¹, the value of enthalpy change for the reaction H₂C = CH₂(g) + H₂(g) → H₃C – CH₃(g) at 298 K will be

-250 kJ

+125 kJ

+250 kJ

-125 kJ

Page 3 of 5

51. ______ is the study about energy of a chemical system

Stoichiometry

Thermodynamics

Thermochemistry

Kinetics

52. The net change in energy in a chemical reaction is same whether it takes place directly or indirectly is

Graham’s law

Henry’s law

Charles’s law

Hess’s law

53. Unit of heat in S.I system is

Cal

Kcal

54. In general, for exothermic reactions to be spontaneous

Temperature should be zero

Temperature should be low

Temperature should be high

Temperature has no effect

55. All of the following are state function except

56. Enthalpy of a reaction can be measured by

Manometer

Thermometer

Barometer

Glass calorimeter

57. Total energy depends upon the state of system

Entropy of reaction

Enthalpy

Free energy of reaction

All above

58. Enthalpy of formation of HF and HCl are – 161 kJ and -92 kJ respectively. Which of the following statements is incorrect?

HF and HCl are endothermic compounds

HCl is more stable than HF

The affinity of fluorine to hydrogen is greater than the affinity of chlorine to hydrogen

HF is more stable than HCl

59. If coefficients of a chemical equation are doubled, the enthalpy change will

Not change

Be double

None of these

Be half

60. Pumping of water uphill is

Non spontaneous

Spontaneous process

Irreversible process

None of these

61. Choose the S.I units for molar heat capacity among the following

Joule cm¯¹ deg¯¹

Joule deg¯¹ mol¯¹

Joule deg¯¹ Kg¯¹

Joule deg¯¹ atom¯¹

62. Four containers hold the following quantity at the same temperature. Which one has the highest heat capacity?

2 kg H₂O

3 kg H₂O

1 kg H₂O

4 kg H₂O

63. If internal energy of a system is increased

Chemical reaction can take place

All

Temperature of the system may rise

Change in state of system can occur

64. Mechanical work is especially important in systems that contain

Solid-solid

Gases

Liquid-liquid

Solid-liquid

65. The heats evolved in combustion of rhombic and monoclinic sulphur are -70960 and -71030 cal mol¯¹ respectively. What will be heat of conversion of rhombic sulphur to monoclinic?

+70 calories

-70 calories

71030 calories

70960 calories

66. Free energy change for a reversible process is:

Equal to zero

Unpredictable

67. The reason of kinetic energy of the molecules of a gaseous substance among the following is

Rotational motion

Translational motion

The sum of all motions which are possible

Vibrational motion

68. In thermodynamics which one of the following is not an intensive property?

Volume

Temperature

Pressure

Density

69. Which one is not a state function?

Work

Gibbs free energy

Internal energy

Enthalpy

70. Which statement describes characteristics of an endothermic reaction?

The sign of H is negative, and the products have less potential energy than the reactants

The sign of H is positive and the products a have more potential energy than the reactant

The sign of H is negative, and the products have more potential energy than the reactants

The sign of H is positive, and the products have less potential energy than the reactants

71. System in which there is no exchange of matter, work or energy from surroundings is

Isolated

Adiabatic

Closed

Isothermal

72. Evaporation of water is

A process where no heat changes occur

A process accompanied by chemical reaction

An exothermic change

An endothermic change

73. 1 mole of H₂SO₄ is mixed with 2 mole of NaOH. The heat evolved will be

57.3 kJ

57.3/2 kJ

Cannot be predicted

2 x 57.3 kJ

74. Total energy of a system is

P.E + heat energy

P.E + mechanical energy

P.E + K.E

K.E + heat energy

75. Which of the following value of ∆Hf’ represent that the product is least stale?

+64.8 kcal mol¯¹

+21.4 kcal mol¯¹

-231.6 kcal mol¯¹

-94.0 kcal mol¯¹

Page 4 of 5

76. A mixture of ice and water contains 60 g of ice and water. If 60 J of heat energy is removed from this mixture, some of the

Ice will melt

Water will vaporize

Water will freeze

Ice will sublime

77. Which of the following is not correct?

Dissolution on NH₄Cl in excess of water is an endothermic process

Neutralization is always exothermic

The heat of reaction at constant volume is denoted by ∆E.

The absolute value of enthalpy (H) can be determined experimentally

78. The S.I unit of heat and energy is

Joules

None of these

Watt

Calorie

79. For a system in equilibrium, ∆ G = 0, under conditions of constant

Pressure and volume

Temperature and volume

Energy and volume

Temperature and pressure

80. The law of Lavoisier and Laplace illustrates

Equivalence of mechanical and thermal energy

The principle of conservation of energy

Equivalent of mechanical and chemical energy

The principle of conservation of matter

81. The reaction is spontaneous if the cell potential is

Positive

Negative

Zero

Infinite

82. A particular reaction has a negative value for the energy change. Then at ordinary temperature

It has a large + ve value for enthalpy change

It has a + ve value for the entropy change and a – ve value for the enthalpy change

It has small + ve value for enthalpy change

It has a large – ve value for the entropy change

83. The heat required to raise the temperature of a body by 1 K is called

Thermal capacity

Specific heat

None of these

Water equivalent

84. The enthalpies of all elements in their standard states are

Negative

Zero

Positive

Unity

85. What is the entropy change (in JK¯¹ mol¯¹) when one mole of ice is converted into water at 0°C? (The enthalpy change for the conversion of ice to liquid water is 6.0 kJ mol¯¹ at 0°C)

2.013

2.198

21.98

20.13

86. The molar heat capacity of water at constant pressure, Cᵨ, is 75 JK¯¹ mol¯¹. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand, the increase in temperature of water is

4.8 K

2.4 K

6.6 K

1.2 K

87. The branch of science which deals with energy transformation is known as

Kinetics

Photochemistry

Thermochemistry

Thermodynamics

88. The unit which indicates the largest amount of energy is

Electron – volt

Calorie

Joule

Erg

89. The law of thermodynamics that provides the basis for the determination of absolute entropy of substance is

Third law

Zeroth law

First law

Second law

90. Change in enthalpy of a system can be calculated by following relationship

∆H = ∆E – d

∆H = ∆E + d

∆H = ∆E – PV

∆H = ∆E + Pv

91. Hess’s law deals with

Equilibrium constant

Rate of reaction

Changes in heat or reaction

Influence of pressure on volume of a gas

92. The best characteristic of spontaneous reactions among the following is that

It is reversible

It is not irreversible

It is irreversible

None of these

93. When enthalpy and entropy change for a chemical reaction are – 2.5 x 10³ cals and 7.4 cals deg¯¹ respectively. Predict that reaction at 298 K is

Irreversible

Non-spontaneous

Spontaneous

Reversible

94. The value of ∆Hо₋н is 109 kcal mol¯¹. Then formation of one mole of water in gaseous state form H(g) and O(g) is accompanied by

Release of 218 kcal of energy

Absorption of 218 kcal of energy

Release of 109 kcal of energy

Unpredictable

95. The enthalpy of formation of carbon monoxide will be

2x – y

2x – y/2

Y – 2x

Y – 2x/2

96. Conversion of copper hydroxide into copper oxide and water is an example of

Respiration

Combustion

Neutralization

Thermal decomposition

97. In endothermic reactions, the heat content of the

Products is more than that of reactants

Reactants is more than that of products

Reactants and products are equal

Both a and b

98. 10.16 g of graphite is burnt in a bomb calorimeter and the temperature rise recorded is 3.78 K. Calculate the enthalpy of combustion of graphite if the heat capacity is 86.02 KJ K¯¹

386 KJ/mole

395 KJ/mole

190 KJ/mole

-27 KJ/mole

99. An exothermic reaction is one in which the reacting substances

Have more energy than the products

Have the same energy as the products

Have less energy than the products

Are at a higher temperature than the products

100. C (diamond) → C(Graphite), ∆ H = -ve. This show that

Both are equally stable

Stability cannot to predicated

Graphite is more stable than diamond

Graphite has more energy than diamond

Page 5 of 5

101. For a given process, the heat changes at constant pressure (q_p) and at constant volume (q_v) are related to each other as:

102. Which one is not state function?

Internal energy

Gibbs free energy

Work

Enthalpy

103. Calorie is equivalent to

4.184 J

0.4184 J

418.4 J

41.84 J

104. Enthalpy of combustion for food, fuel and other compounds can be measured accurately by

Glass Calorimeter

Thermometer

Bomb Calorimeter

Monometer

105. A cylinder of gas supplied by PSO is assumed to contain 14 kg of butane. If a normal family requires 20,000 kJ of energy per day for cooking, butane gas in the cylinder last for ……. Days (∆Hc of C₄H₁₀ = -2658 kJ per mole)

15 days

50 days

20 days

32 days

106. The internal energy change when a system goes form state A to B is 40 kJ.mol. If the system goes from A to B by a reversible path and returns to state A by an irreversible path what would be the net change in internal energy?

> 40 kJ

< 40 kJ

Zero

40 kJ

107. One of the statement about Born Haber cycle is correct. Which is that statement?

Heat of formation of the product and lattice energy of the substance can be calculated simultaneously

The lattice energy of the crystalline substances can be calculated easily

Born Haber cycle is different from Hess’s law

The energy change in a cyclic process is not zero

108. What type of chemical reaction absorbs energy and requires energy for the reaction occur?

Exothermic

Synthesis

Both a and b

Endothermic

You Can Learn and Gain more Knowledge through our Online Quiz and Testing system Just Search your desired Preparation subject at Gotest.

UET Peshawar Entry Test 2025 Registration Online ETEA Test D...
ECAT Statistics Test Set 17
ECAT Statistics Test Set 16
ECAT Statistics Test Set 15
ECAT Statistics Test Set 14
ECAT Statistics Test Set 13
ECAT Statistics Test Set 12
ECAT Statistics Test Set 11
ECAT Statistics Test Set 10
ECAT Statistics Test Set 9

Maan AliLast Updated: April 19, 2025

Facebook Twitter Reddit WhatsApp Share via Email Print

ECAT Chemistry Thermochemistry Online Test

Chemistry Thermochemistry MCQS Online Test

ECAT Chemistry Thermochemistry Chapter Online Test

ECAT Chemistry Thermochemistry Test

Chemistry

You Might Also Like

Maan Ali

2 Comments

Leave a Reply Cancel reply