One mole of an ideal gas at 300 K is expanded isothermally from an initial volume of 1 litre to 10 litres. The ∆E for this process is:
(R = 2 cal. $mo{l}^{-1}{K}^{-1}$)
1. 1381.1 cal.
2. Zero
3. 163.7 cal.
4. 9 lit. atm

If the bond energies of H–H, Br – Br, and H –Br are 433, 192, and 364 kJ mol^–1 respectively, the ∆Hº for the reaction H₂(g) + Br₂(g) → 2HBr(g) will be:

1. +103 kJ

2. +261kJ

3. –103 kJ

4. –261 kJ 

What is true for a cyclic process:

1.  a, b
2.  b, c
3.  c, d
4.  a, d

If a system is expanded under adiabatic process, then:

1.  Temperature increases
2.  ∆E decreases
3.  ∆E increases
4.  None of the above

Which of the following is true for a reaction in which all the reactants & products are liquids:
1.  ∆H = ∆E
2.  ∆H = ∆W
3.  ∆H > ∆E
4.  None of the above

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

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

The standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are –382.64 kJ mol^–1 and –145.6 JK^–1 mol^–1, respectively. Standard Gibbs energy change for the same reaction at 298 K is:

1. –339.3 kJ mol^–1

2. – 439.3 kJ mol^–1

3. –523.2 kJ mol^–1

4. –221.1 kJ mol^–1

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. –608 J

2. +304 J

3. –304 J

4. –6 J 

$2Zn+O_2\to 2ZnO$ $$ $$ $$ $∆G°=-616$ $J$
$2Zn+S_2\to 2ZnS$ $$ $$ $$ $$ $∆G°=-293$ $J$
$S_2+2O_2\to 2S{O}_2$ $$ $$ $$ $$ $∆G°=-408J$

$∆G°$ for the following reaction is:

$2ZnS+3O_2\to 2ZnO+2S{O}_2$

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