For the reaction, 2Cl(g) $\to$ Cl₂(g), the correct option is:

1. ${∆}_{\mathrm{r}}\mathrm{H}>0<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{∆}_{\mathrm{r}}\mathrm{S}<0$

2. ${∆}_{\mathrm{r}}\mathrm{H}<0<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{∆}_{\mathrm{r}}\mathrm{S}>0$

3. ${∆}_{\mathrm{r}}\mathrm{H}<0<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{∆}_{\mathrm{r}}\mathrm{S}<0$

4. ${∆}_{\mathrm{r}}\mathrm{H}>0<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{∆}_{\mathrm{r}}\mathrm{S}>0$

The correct option for free expansion of an ideal gas under adiabatic condition is:

1.  $q=0,$ $∆T<0$ and $w>0$

2.  $q<0,$ $∆T=0$ and $w=0$

3.  $q>0,$ $∆T>0$ and $w>0$

4.  $q=0,$ $∆T=0$ and $w=0$

The solubility of a solute in water varies with temperature and is given as $\mathrm{S}={\mathrm{Ae}}^{-∆\mathrm{H}/\mathrm{RT}}.$

Here, $∆\mathrm{H}$ is enthalpy of the solution. For the given solute variation of log, S with temperature can be shown by the figure given below.

This solute may be

1. CaSO₄ 

2. CuSO₄ 

3. CuSO₄5H₂O

5. MgO

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

$$\begin{gathered} \left(1\right)<mspace\; width="1em"></mspace>{(∆\mathrm{U}/∆\mathrm{T})}_{\mathrm{v}} \\ <mspace\; width="1em"></mspace>\left(2\right)<mspace\; width="1em"></mspace>{(∆\mathrm{H}/∆\mathrm{T})}_{\mathrm{V}}<mspace\; width="1em"></mspace> \\ \left(3\right)<mspace\; width="1em"></mspace>{(∆\mathrm{H}/∆\mathrm{T})}_{\mathrm{P}}<mspace\; width="1em"></mspace> \\ \left(4\right)<mspace\; width="1em"></mspace>{(∆U/∆\mathrm{T})}_{\mathrm{P}} \end{gathered}$$

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) $\frac{∆V}{V}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

(2) $<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>-y\frac{∆V}{V}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

(3) $<mspace\; width="1em"></mspace>y\frac{∆V}{V}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

(4) $<mspace\; width="1em"></mspace>-y^2\frac{∆V}{V}<mspace\; width="1em"></mspace>$

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