In Dumas' method for estimation of nitrogen, 0.5 gram of an organic compound gave 60 mL of nitrogen collected at 300 K temperature and 715 mm Hg pressure. The percentage composition of nitrogen in the compound (Aqueous tension at $300 \mathrm{~K}=15 \mathrm{~mm} \mathrm{Hg}$ ) is___________%.

Which of the following statements are true?

(A) The subsidiary quantum number $l$ describes the shape of the orbital occupied by the electron.

(B) is the boundary surface diagram of the $2 \mathrm{p}_x$ orbital.

(C) The + and - signs in the wave function of the $2 p_x$ orbital refer to charge.

(D) The wave function of $2 \mathrm{p}_x$ orbital is zero everywhere in the $x y$ plane.

Choose the correct answer from the options given below :

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