At $$-20^{\circ} \mathrm{C}$$ and $$1 \mathrm{~atm}$$ pressure, a cylinder is filled with equal number of $$\mathrm{H}_2, \mathrm{I}_2$$ and $$\mathrm{HI}$$ molecules for the reaction $$\mathrm{H}_2(\mathrm{~g})+\mathrm{I}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g})$$, the $$\mathrm{K}_{\mathrm{p}}$$ for the process is $$x \times 10^{-1}$$.

$$\mathrm{x}=$$ __________.

[Given : $$\mathrm{R}=0.082 \mathrm{~L} \mathrm{~atm} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$$]

The electron affinity value are negative for

A. $$\mathrm{Be} \rightarrow \mathrm{Be}^{-}$$

B. $$\mathrm{N} \rightarrow \mathrm{N}^{-}$$

C. $$\mathrm{O} \rightarrow \mathrm{O}^{2-}$$

D. $$\mathrm{Na} \rightarrow \mathrm{Na}^{-}$$

E. $$\mathrm{Al} \rightarrow \mathrm{Al}^{-}$$

Choose the most appropriate answer from the options given below :

Consider the following complexes

(A) $$\left[\mathrm{CoCl}\left(\mathrm{NH}_3\right)_5\right]^{2+}$$, (B) $$\left[\mathrm{Co}(\mathrm{CN})_6\right]^{3-}$$, (C) $$ \left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5\left(\mathrm{H}_2 \mathrm{O}\right)\right]^{3+} $$, (D) $$\left[\mathrm{Cu}\left(\mathrm{H}_2 \mathrm{O}\right)_4\right]^{2+}$$

The correct order of A, B, C and D in terms of wavenumber of light absorbed is :

Functional group present in sulphonic acids is :