PART - 1 CH - 5 Thermodynamics — Chemistry STD 11 Science — Question

$\text{CCI}_4(\text{g})\xrightarrow{ \ \ \ \ \ }\text{C}(\text{g})+4\text{CI}(\text{g})$

$\Delta_\text{vap}\text{H}^\ominus(\text{CCI}_4)=30.5\text{kJ} \ \text{mol}^{-1}.$

$\Delta_\text{f}\text{H}^\ominus(\text{CCI}_4)=-135.5\text{kJ} \ \text{mol}^{-1}.$

$\Delta_\text{a}\text{H}^\ominus(\text{C})=-715.0\text{kJ} \ \text{mol}^{-1},$ where $\Delta_\text{a}\text{H}^\ominus$ is enthalpy of atomisation

$\Delta_\text{a}\text{H}^\ominus(\text{CI}_2)=242\text{kJ} \ \text{mol}^{-1}$

1. Write the conjugate acid of NH₃.
2. Assign reason for the following:

1. A solution of NH₄Cl in water shows pH less than 7.
2. In qualitative analysis NH₄Cl is added before adding NH₄OH for testing Fe³⁺ or AP³⁺ ions.

3. Consider the reaction:

$\text{N}_2(\text{g})+3\text{H}_2\text{(g)}\rightleftharpoons2\text{NH}_3+\text{Heat}$

Indicate the direction in which the equilibrium will shift when:

1. Temperature is increased.
2. Pressure is increased.