Arrange the following in order of magnitude of work done by the system/on the system at constant temperature.

(a) $\left|w_{\text {reversible }}\right|$ for expansion in infinite stages.

(b) $\left|w_{\text {irreversible }}\right|$ for expansion in single stage.

(c) $\left|\mathrm{w}_{\text {reversible }}\right|$ for compression in infinite stages.

(d) $\left|w_{\text {irreversible }}\right|$ for compression in single stage.

Choose the correct answer from the options given below :

Which of the following graphs correctly represents the variation of thermodynamic properties of Haber's process?

Two vessels A and B are connected via stopcock. The vessel A is filled with a gas at a certain pressure. The entire assembly is immersed in water and is allowed to come to thermal equilibrium with water. After opening the stopcock the gas from vessel A expands into vessel B and no change in temperature is observed in the thermometer. Which of the following statement is true ?

If $\quad C$ (diamond $) \rightarrow C$ (graphite) $+X \mathrm{~kJ} \mathrm{~mol}^{-1}$

C (diamond) $+\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})+\mathrm{Y} \mathrm{kJ} \mathrm{mol}{ }^{-1}$

C (graphite) $+\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})+\mathrm{Z} \mathrm{kJ} \mathrm{mol}^{-1}$

at constant temperature. Then