The enthalpy of vapourization water is 386 kJ. What is the entropy of water [BHU 1997]

(1) 0.5 kJ

(2) 1.03 kJ

(3) 1.5 kJ

(4) 22.05 kJ

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Identify the correct statement regarding entropy [CBSE PMT 1998; BHU 2001]

(1) At 0°C, the entropy of a perfectly crystalline substance is taken to be zero

(2) At absolute zero of temperature, the entropy of a perfectly crystalline substance is +ve

(3) At absolute zero of temperature, the entropy of all crystalline substances is taken to be zero

(4) At absolute zero of temperature, the entropy of a perfectly crystalline substance is taken to be zero

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

An engine operating between 150°C and 25°C takes 500 J heat from a higher temperature reservoir if there are no frictional losses, then work done by engine is [MH CET 1999]

(1) 147.7 J

(2) 157.75 J

(3) 165.85 J

(4) 169.95 J

Concept Questions :-

First Law of Thermodynamics
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The standard entropies of CO2(g), C(s) and O2(g) are 213.5, 5.690 and 205 JK–1 respectively. The standard entropy of formation of CO2(g) is [CPMT 2001]

(1) 1.86 JK–1

(2) 1.96 JK–1

(3) 2.81 JK–1

(4) 2.86 JK–1

Concept Questions :-

Thermochemistry
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Difficulty Level:

Equal volumes of monoatomic and diatomic gases at same initial temperature and pressure are mixed. The ratio of specific heats of the mixture (Cp/Cv) will be [AFMC 2002]

(1) 1

(2) 2

(3) 1.67

(4) 1.5

Concept Questions :-

CP and CV and Relation for Real Gas
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The unit of entropy is [CBSE PMT 2002]

(1) J mol–1

(2) JK mol–1

(3) J mol–1 K–1

(4) J–1 K–1 mol–1

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The entropy changed involved in the conversion of 1 mole of liquid water at 373 K to vapour at the same temperature will be $\left[\Delta {H}_{\text{vap}}=2.257kJ/gm\right]$ [MP PET 2002]

(1) 0.119 kJ

(2) 0.109 kJ

(3) 0.129 kJ

(4) 0.120 kJ

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

When a liquid boils, there is [JIPMER 2002]

(1) An increase in entropy

(2) A decrease in entropy

(3) An increase in heat of vaporization

(4) An increase in free energy

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The work done to contract a gas in a cylinder, is 462 joules. 128 joule energy is evolved in the process. What will be the internal energy change in the process [MP PMT 2003]

(1) + 590 joules

(2) – 334 joules

(3) + 334 joules

(4) – 590 joules

Concept Questions :-

Internal Energy and work done
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

For a carnot engine, the source is at 500 K and the sink at 300 K. What is efficiency of this engine [BHU 2004]

(1) 0.2

(2) 0.4

(3) 0.6

(4) 0.3

Concept Questions :-

Enthalpy and It's Type