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 :

When a concentrated solution of sulphanilic acid and 1-naphthylamine is treated with nitrous acid $(273 \mathrm{~K})$ and acidified with acetic acid, the mass $(\mathrm{g})$ of 0.1 mole of product formed is :

(Given molar mass in $\mathrm{g} \mathrm{mol}^{-1} \mathrm{H}: 1, \mathrm{C}: 12, \mathrm{~N}: 14, \mathrm{O}: 16, \mathrm{~S}: 32$ )

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

Reactant A converts to product D through the given mechanism (with the net evolution of heat):

A → B     slow;     ΔH = +ve

B → C     fast;     ΔH = -ve

C → D     fast;     ΔH = -ve

Which of the following represents the above reaction mechanism?