The correct sequence of electron gain enthalpy of the elements listed below is

A. Ar

B. Br

C. F

D. S

Choose the most appropriate from the options given below:

Consider the following reaction at $$298 \mathrm{~K} \cdot \frac{3}{2} \mathrm{O}_{2(g)} \rightleftharpoons \mathrm{O}_{3(g)} \cdot \mathrm{K}_{\mathrm{P}}=2.47 \times 10^{-29}$$. $$\Delta_r G^{\ominus}$$ for the reaction is _________ $$\mathrm{kJ}$$. (Given $$\mathrm{R}=8.314 \mathrm{~JK}^{-1} \mathrm{~mol}^{-1}$$)

The product of the following reaction is P.

The number of hydroxyl groups present in the product P is ________.

The ionization energy of sodium in $$\mathrm{~kJ} \mathrm{~mol}^{-1}$$, if electromagnetic radiation of wavelength $$242 \mathrm{~nm}$$ is just sufficient to ionize sodium atom is _______.