In an isothermal change, an ideal gas obeys:

1.	Boyle's law	2.	Charles law
3.	Gay-Lussac law	4.	None of the above

For the reaction, $2{\mathrm{N}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{N}}_2\mathrm{O}\left(\mathrm{g}\right)$, at 298K $∆\mathrm{H}$ is 164 kJ mol^-1. The $∆\mathrm{E}$ of the reaction is-
1. \(166.5 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
2. \(141.5 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
3. \(104.0 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
4. \(-169 \mathrm{~kJ} \mathrm{~mol}^{-1}\)

The bond energies of $\mathrm{C}\equiv \mathrm{C}$, C-H, H-H, and C=C are 198, 98, 103, and 145 kcal respectively.

The enthalpy change of the reaction $\mathrm{HC}\equiv \mathrm{CH}+{\mathrm{H}}_2\to {\mathrm{C}}_2{\mathrm{H}}_4$ would be:

1. 48 kcal

2. 96 kcal

3. -40 kcal

4. -152 kcal

Which among the following state functions is an extensive property of the system?

For a sample of a perfect gas when its pressure is changed isothermally from P_i to P_f, the entropy change is given by:

1. $∆\mathrm{s}=\mathrm{nR}$ $\mathrm{In}$ $\left(\frac{{\mathrm{p}}_{\mathrm{f}}}{{\mathrm{p}}_{\mathrm{i}}}\right)$

2. $∆\mathrm{s}=\mathrm{nR}$ $\mathrm{In}$ $\left(\frac{{\mathrm{p}}_{\mathrm{i}}}{{\mathrm{p}}_{\mathrm{f}}}\right)$

3. $∆\mathrm{s}=\mathrm{nRT}$ $\mathrm{In}$ $\left(\frac{{\mathrm{p}}_{\mathrm{f}}}{{\mathrm{p}}_{\mathrm{i}}}\right)$

4. $∆\mathrm{s}=\mathrm{RT}$ $\mathrm{In}$ $\left(\frac{{\mathrm{p}}_{\mathrm{i}}}{{\mathrm{p}}_{\mathrm{f}}}\right)$

For a given reaction, ∆H = 35.5 kJ mol^–1 and ∆S = 83.6 J K^–1 mol^–1. The reaction is spontaneous at:
(Assume that ∆H and ∆S  do not vary with temperature)
1. T > 425K
2. All temperatures
3. T > 298K
4. T < 425K

The enthalpy and entropy change for the reaction :

Br₂ (l) + Cl₂ (g)$\to$ 2BrCl (g)

are 30 kJ mol^-1 and 105 J K^-1 mol^-1 respectively.

The temperature at which the reaction will be in equilibrium is :

The bond dissociation energies of $X_2 , Y_2$ and XY are in the ratio of 1 : 0.5 : 1. ∆H for the formation of XY is –200 kJ mol^–1. The bond dissociation energy of X₂ will be

The heat of combustion of carbon to CO₂ is –393.5 KJ/mol. The heat released upon the formation of 35.2 g of CO₂ from carbon and oxygen gas is:
1. –315 KJ
2. +315 KJ
3. –630 KJ
4. +630 KJ