At 27ºC latent heat of fusion of a compound is 2930 J/mol. Entropy change is:

1. 9.77 J/mol K

2. 10.77 J/mol K

3. 9.07 J/mol K

4. 0.977 J/mol K

Unit of entropy is:

1. JK^–1 mol^–1

2. J mol^–1

3. J^–1K^–1 mol^–1

4. JK mol^–1

2 mole of an ideal gas at 27ºC temp. is expanded reversibly from 2 lit. to 20 lit. Find entropy change (R = 2 cal/mol K): 

1. 92.1

2. 0

3. 4

4. 9.2

What is the entropy change (in JK^–1 mol^–1) when one mole of ice is converted into water at 0 ºC? (The enthalpy change for the conversion of ice to liquid water is 6.0 KJ mol^–1 at 0 ºC)

Considering entropy (S) as a thermodynamic parameter, the criterion for the spontaneity of any process is:

1. ${\mathrm{\Delta S}}_{\mathrm{system }}-{\mathrm{\Delta S}}_{\mathrm{surrounding }}>0$

2. ${\mathrm{\Delta S}}_{\mathrm{system }}>0\mathrm{ only }$

3. ${\mathrm{\Delta S}}_{\mathrm{surroundings }}>\mathrm{0}$ $\mathrm{only}$

4. ${\mathrm{\Delta S}}_{\mathrm{system }}+{\mathrm{\Delta S}}_{\mathrm{surrounding }}>0$

A reaction occurs spontaneously if:

1. T∆S > ∆H and ∆H is +ve and ∆S are –ve

2. T∆S = ∆H and both ∆H and ∆S are +ve

3. T∆S < ∆H and both ∆H and ∆S are +ve

4. T∆S > ∆H and both ∆H and ∆S are +ve

Which of the following pairs of chemical reactions is certain to result in a spontaneous reaction:

1. Endothermic and decreasing disorder

2. Exothermic and increasing disorder

3. Endothermic and increasing disorder

4. Exothermic and decreasing disorder