CBSE Class 11 Chemistry Thermodynamics Worksheet

Thermodynamics MCQ Questions with Answers Class 11 Chemistry 

Question- The system that would not allow exchange of heat between the system and surroundings through its boundary is considered as

(a) isothermal

(b) adiabatic

(c) isobaric

(d) isochoric

Answer-(b)

Question-The universe refers to

(a) only system

(b) only surroundings

(c) both system and surroundings

(d) None of these

Answer-(c)

Question- ………………. is a quantity which represents the total energy of the system

(a) Internal energy

(b) Chemical energy

(c) Electrical energy

(d) Mechanical energy

Answer-(a)

Question-Which of the following statements is correct?

(a) The presence of reacting species in a covered beaker is an example of open system.

(b) There is an exchange of energy as well as matter between the system and the surroundings in a closed system.

(c) The presence of reactants in a closed vessel made up of copper is an example of a closed system.

(d) The presence of reactants in a thermos flask or any other closed insulated vessel is an example of a closed system.

Answer-(c)

Question- Which ofthe following is closed system ?

(a) Jet engine

(b) Tea placed in a steel kettle

(c) Pressure cooker

(d) Rocket engine during propulsion

Answer-(c)

Question-Which of the following statements is not true regarding the laws of thermodynamics ?

(a) It deal with energy changes of macroscopic systems.

(b) It deal with energy changes of microscopic systems.

(c) It does not depends on the rate at which these energy transformations are carried out.

(d) It depends on initial and final states of a system undergoing the change.

Answer-(b)

Question-The state of a thermodynamic system is described by its measurable or macroscopic (bulk) properties. These are

(a) Pressure and volume

(b) Pressure, volume, temperature and amount

(c) Volume, temperature and amount

(d) Pressure and temperature

Answer-(b)

Question-Which of the following are not state functions ?
(I) q + w (II) q
(III) w (IV) H - TS

(a) (I) and (IV)

(b) (II), (III) and (IV)

(c) (I), (II) and (III)

(d) (II) and (III)

Answer-(d)

Question-Enthalpy change ( ΔH) of a system depends upon its

(a) Initial state

(b) Final state

(c) Both on initial and final state

(d) None of these

Answer-(c)

Question-Which of the following factors affect the internal energy of the system ?

(a) Heat passes into or out of the system.

(b) Work is done on or by the system.

(c) Matter enters or leaves the system.

(d) All of the above

Answer-(d)

Question-Thermodynamics is not concerned about____.

(a) energy changes involved in a chemical reaction.

(b) the extent to which a chemical reaction proceeds.

(c) the rate at which a reaction proceeds

(d) the feasibility of a chemical reaction.

Answer-(c)

Question- The enthalpy change of a reaction does not depend on

(a) The state of reactants and products

(b) Nature of reactants and products

(c) Different intermediate reactions

(d) Initial and final enthalpy change of a reaction.

Answer-(c)

Question- A……………... in thermodynamics refers to that part of universe in which observations are made and remaining universe constitutes the……………...

(a) surroundings, system

(b) system, surroundings

(c) system, surroundings

(d) system, boundary

Answer-(b)

Question-An isolated system is that system in which

(a) There is no exchange of energy with the surroundings

(b) There is exchange of mass and energy with the surroundings

(c) There is no exchange of mass or energy with the surroundings

(d) There is exchange of mass with the surroundings

Answer-(c)

Question- Among the following the state function(s) is (are)

(i) Internal energy
(ii) Irreversible expansion work
(iii) Reversible expansion work
(iv) Molar enthalpy

(a) (ii) and (iii)

(b) (i), (ii) and (iii)

(c) (i) and (iv)

(d) (i) only

Answer-(c)

Thermodynamics MCQ Questions with Answers Class 11 Chemistry 

Question- The q is ……………. when heat is transferred from the surroundings to the system and q is……………………….. When heat is transferred from system to the surroundings.

(a) positive , negative

(b) negative , positive

(c) high, low

(d) low, high

Answer-(a)

Question- The heat required to raise the temperature of body by 1 C° is called

(a) specific heat

(b) thermal capacity

(c) water equivalent

(d) None of these

Answer-(b)

Question- The work done during the expansion of a gas from a volume of 4 dm3 to 6 dm3 against a constant external pressure of 3 atm is (1 L atm = 101.32 J)

(a) – 6 J

(b) – 608 J

(c) + 304 J

(d) – 304 J

Answer-(b)

Question- The molar heat capacity of water at constant pressure is 75 JK^–1 mol^–1. When 1kJ of heat is supplied to 100 g of water, which is free to expand, the increase in temperature of water is

(a) 6.6 K

(b) 1.2 K

(c) 2.4 K

(d) 4.8 K

Answer-(c)

Question- An ideal gas expands in volume from 1×10^–3 to 1 × 10^–2 m³ at 300 K against a constant pressure of 1×10⁵ Nm^–2. The work done is

(a) 270 kJ

(b) – 900 kJ

(c) – 900 J

(d) 900 kJ

Answer-(c)

Question- For a reaction in which all reactants and products are liquids,which one of the following equations is most applicable ?

(a) ΔH < ΔE

(b) ΔH = ΔS

(c) ΔH = ΔE

(d) ΔH = ΔG

Answer-(c)

Question- Adiabatic expansions of an ideal gas is accompanied by

(a) decrease in ΔE

(b) increase in temperature

(c) decrease in ΔS

(d) no change in any one of the above properties

Answer-(a)

Question- Which is an extensive property of the system ?

(a) Volume

(b) Viscosity

(c) Temperature

(d) Refractive index

Answer-(a)

Question- During isothermal expansion of an ideal gas, its

(a) internal energy increases

(b) enthalpy decreases

(c) enthalpy remains unaffected

(d) enthalpy reduces to zero.

Answer-(c)

Question- Which of the following statements is incorrect?

(a) q is a path dependent function.

(b) H is a state function.

(c) Both H and q are state functions.

(d) Both (a) and (b)

Answer-(d)

Question- Which of the following is an example of extensive property?

(a) Temperature

(b) Density

(c) Mass

(d) Pressure

Answer-(c)

Question-  Which of the following factors do not affect heat capacity?

(a) Size of system

(b) Composition of system

(c) Nature of system

(d) Temperature of the system

Answer-(d)

Question- Equal volumes of two monoatomic gases, A and B, at same temperature and pressure are mixed. The ratio of specific heats (Cp/Cv) of the mixture will be :

(a) 0.83

(b) 1.50

(c) 3.3

(d) 1.67

Answer-(d)

Question- Among the following, the intensive properties are
(i) molar conductivity (ii) electromotive force
(iii) resistance (iv) heat capacity

(a) (ii) and (iii)

(b) (i), (ii) and (iii)

(c) (i) and (iv)

(d) (i) only

Answer-(a)

Question- Calorie is equivalent to :

(a) 0.4184 Joule

(b) 4.184 Joule

(c) 41.84 Joule

(d) 418.4 Joule

Answer-(b)

Thermodynamics MCQ Questions with Answers Class 11 Chemistry 

Question- Identify the correct statement regarding a spontaneous process:

(a) Lowering of energy in the process is the only criterion for spontaneity.

(b) For a spontaneous process in an isolated system, the change in entropy is positive.

(c) Endothermic processes are never spontaneous.

(d) Exothermic processes are always spontaneous.

Answer-(b)

Question-The enthalpies of elements in their standard states are taken as zero. The enthalpy of formation of a compound

(a) is always negative

(b) is always positive

(c) may be positive or negative

(d) is never negative

Answer-(c)

Question- Pick out the wrong statement

(a) The standard free energy of formation of all elements is zero

(b) A process accompanied by decrease in entropy is spontaneous under certain conditions

(c) The entropy of a perfectly crystalline substance at absolute zero is zero

(d) A process that leads to increase in free energy will be spontaneous

Answer-(d)

Question- Bond dissociation enthalpy of H₂, Cl₂ and HCl are 434 , 242 and 431 kJ mol^–1 respectively. Enthalpy of formation of HCl is:

(a) 93 kJ mol^–1

(b) – 245 kJmol^–1

(c) – 93 kJmol^–1

(d) 245 kJmol^–1

Answer-(c)

Question-The enthalpy change on breaking one mole of bonds completely to obtain atoms in the gas phase is known as

(a) enthalpy of atomization.

(b) enthalpy of formation

(c) enthalpy of sublimation

(d) enthalpy of vaporization

Answer-(a)

Question-The enthalpy change for a reaction does not depend upon

(a) use of different reactants for the same product

(b) the nature of intermediate reaction steps

(c) the differences in initial or final temperatures of involved substances

(d) the physical states of reactants and products

Answer-(b)

Question-The heat of combustion of a substance is :

(a) Always positive

(b) Always negative

(c) Numerically equal to the heat of formation

(d) Unpredictable

Answer-(b)

Question-Given that heat of neutralisation of strong acid and strong base is – 57.1 kJ. The heat produced when 0.25 mole of HCl is neutralised with 0.25 mole of NaOH in aqueous solution is :

(a) 14.275 kJ

(b) 57.1 kJ

(c) 22.5 kJ

(d) 28.6 kJ

Answer-(a)

Question-Hess’s law is used to calculate :

(a) enthalpy of reaction.

(b) entropy of reaction

(c) work done in reaction

(d) All of the above

Answer-(a)

Question-For most of the ionic compounds, sol ΔH is …………and the dissociation process is…………….

(a) positive ,exothermic

(b) negative, exothermic

(c) positive, endothermic

(d) negative,endothermic

Answer-(c)

Question-A chemical reaction will be spontaneous if it is accompanied by a decrease of

(a) entropy of the system.

(b) enthalpy of the system.

(c) internal energy of the system.

(d) free energy of the system.

Answer-(d)