The equilibrium constant for the reaction

${\mathrm{H}}_2\left(\mathrm{g}\right)+\mathrm{S}\left(\mathrm{g}\right)\rightleftharpoons {\mathrm{H}}_2\mathrm{S}\left(\mathrm{g}\right)$

is 18.5 at 925 and 9.25 at 1000 respectively. What is the enthalpy of the reaction?

1. -142.16 kJ/mole

2. -71.08 kJ/mole

3. -35.54 kJ/mole

4. none of these

If the value of $∆$H in a reaction is positive, then the reaction is called

(1) Exothermic

(2) Endothermic

(3) Polymorphic

(4) Polytropic

Molar heat capacity at constant P for a substance is equal to

$$\begin{gathered} \left(1\right) {(∆\mathrm{U}/∆\mathrm{T})}_{\mathrm{v}} \\ \left(2\right) {(∆\mathrm{H}/∆\mathrm{T})}_{\mathrm{V}} \\ \left(3\right) {(∆\mathrm{H}/∆\mathrm{T})}_{\mathrm{P}} \\ \left(4\right) {(∆U/∆\mathrm{T})}_{\mathrm{P}} \end{gathered}$$

Plants and living beings are examples of:
1. Isolated system
2. Adiabatic system
3. Open system
4. Closed system

For an adiabatic expansion of a perfect gas, $∆$P/P is equal to?

(1) $\frac{∆V}{V}$

(2) $-y\frac{∆V}{V}$

(3) $y\frac{∆V}{V}$

(4) $-y^2\frac{∆V}{V}$

What happens to a gas when it expands at constant temperature and pressure?

1. Internal energy decreases

2. Entropy increases and then decreases

3. Internal energy increases

4. Internal energy remains constant

If a gas absorbs 200 J of heat and expands by 500 ${\mathrm{cm}}^3$ against the constant pressure of 2x${10}^5$ Nm^-2 , then the change in internal energy is :

1. $-$200 J

2. $-$100J

3. +100J

4. + 300J

The internal energy of a substance does not depend upon

(1) Translational energy

(2) Vibrational energy

(3) Energy due to the gravitational pull

(4) Rotational energy

Internal energy (E) and pressure of a gas of unit volume are related

as

(1) $P=\frac{2}{3}E$
$$

(2) $P=\frac{3}{2}E$

(3) $P=\frac{E}{2}$

(4) P=2E

Identify the false statement among the following.