Assume each reaction is carried out in an open container. For which of the following reactions will $∆\mathrm{H\; be\; equal\; to }∆\mathrm{U}?$

1. ${\mathrm{PCl}}_3\left(\mathrm{g}\right)$ $\to {\mathrm{PCl}}_3\left(\mathrm{g}\right)$ $+{\mathrm{Cl}}_2\left(\mathrm{g}\right)$ $$

2. $2\mathrm{CO}\left(\mathrm{g}\right)$ $+{\mathrm{O}}_2\left(\mathrm{g}\right)$ $\to 2{\mathrm{CO}}_2\left(\mathrm{g}\right)$ $$

3. ${\mathrm{H}}_2\left(\mathrm{g}\right)$ $+{\mathrm{Br}}_2\left(\mathrm{g}\right)$ $\to 2\mathrm{HBr}\left(\mathrm{g}\right)$

4. $\mathrm{C}\left(\mathrm{s}\right)$ $+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)$ $\to 2{\mathrm{H}}_2\left(\mathrm{g}\right)$ $+{\mathrm{CO}}_2\left(\mathrm{g}\right)\hspace{0.17em}$

Which of the following is not an endothermic reaction?

1. Combustion of methane

2. Decomposition of water

3. Dehydrogenation of ethane or ethylene

4. Conversion of graphite to diamond

The enthalpies of formation of Al₂O₃ and Cr₂O₃ are – 1596 kJ and – 1134 kJ, respectively. ∆H for the reaction 2Al + Cr₂O₃ → 2Cr + Al₂O₃ is -

Hydrolysis of sucrose is given by the following reaction

Sucrose + H₂O $\rightleftharpoons$ Glucose + Fructose

If the equilibrium constant (K_c) is 2$\times$10¹³ at 300 K, the value of ${∆}_r{G}^{⊝}$ at the same temperature will be:

1. 8.314 J mol^–1 K^–1$\times$300 K$\times$ln (2$\times$10¹³)

2. 8.314 J mol^–1 K^–1$\times$300 K$\times$ln (3$\times$10¹³)

3. –8.314 J mol^–1 K^–1$\times$300 K$\times$ln (4$\times$10¹³)

4. –8.314 J mol^–1 K^–1$\times$300 K$\times$ln (2$\times$10¹³)

For the reaction, $2C{}^{}\to C{}^{}$, the value of ∆H and ∆S  are respectively -

1. $∆\mathrm{H}=0$ $,$ $∆\mathrm{S}=-\mathrm{ve}$

2. $∆\mathrm{H}=0$ $,$ $∆\mathrm{S}=0$

3. $∆\mathrm{H}=$ $-\mathrm{ve}$ $,$ $∆\mathrm{S}$ $=$ $-\mathrm{ve}$

4. $∆\mathrm{H}=$ $+\mathrm{ve}$ $,$ $∆\mathrm{S}=$ $+\mathrm{ve}$

When 4 g of iron is burnt to ferric oxide at a constant pressure, 29.28 kJ of heat is evolved.

The enthalpy of formation of ferric oxide will be-

(At. mass of Fe = 56) ?

1. $-$81.98 kJ

2. $-$ 819.8 kJ

3. $-$ 40.99 kJ

4.  +819.8 kJ

Match the following process with entropy change

Codes

Match the following parameters with a description for spontaneity.

Codes

Thermodynamics is not concerned about-

1. Energy changes involved in a chemical reaction

2. The extent to which a chemical reaction proceeds

3. The rate at which a reaction proceeds

4. The feasibility of a chemical reaction