Thermodynamics Test for Class 11

Third law of thermodynamics provides a method to evaluate which property?

• Absolute Energy

• Absolute Enthalpy

• Absolute Entropy

• Absolute Free Energy

One mole of which of the following has the highest entropy?

• Liquid Nitrogen

• Hydrogen Gas

• Mercury

• Diamond

The enthalpy of vaporisation of a substance is 8400 J mol-1 and its boiling point is –173°C. The entropy change for vaporisation is:

• 12 J mol-1K-1

• 49 J mol-1K-1

• 21 J mol-1K-1

• 84 J mol-1K-1

The species which by definition has ZERO standard molar enthalpy of formation at 298 K is:

• H2O(g)

• CH4(g)

• Br2(g)

• Cl2(g)

In a reversible process the system absorbs 600 kJ heat and performs 250 kJ work on the surroundings. What is the increase in the internal energy of the system?

• 850 kJ

• 600 kJ

• 350 kJ

• 250 kJ

Which of the following is true for the reaction? H2O (l) ↔ H2O (g) at 100° C and 1 atm pressure?

• ∆S = 0

• ∆H = T ∆S

• ∆H = ∆U

• ∆H = 0

Calculate the heat required to make 6.4 Kg CaC2 from CaO(s) and C(s).

• 86.24 × 10³

• 1100 kcal

• 1.11 × 104 kcal

• 5624 kcal

In a system where ∆E = -51.0 kJ, a piston expanded against a pext of 1.2 atm giving a change in volume of 32.0 L. What was the change in heat of this system?

• -13 kJ

• -36 kJ

• 24 kJ

• -47 kJ

A system absorbs 10 kJ of heat at constant volume and its temperature rises from 270 C to 370 C. The value of ∆ U is:

• 1 kJ

• 0 kJ

• 10 kJ

• 100 kJ

An ideal gas is taken around the cycle ABCA as shown in P-V diagram. The work done by the gas during the cycle is equal to:

• 5P1V1

• P1V1

• 6P1V1

• 12P1V1