MCQ
Select the gas-phase reaction$(s)$ which can proceed spontaneously ?
- A$C{l^ - } + I \to {I^ - } + Cl$
- B$S{i^ + } + Cl \to Si + C{l^ + }$
- CBoth $(A)$ and $(B)$
- ✓$Kr + H{e^ + } \to K{r^ + } + He$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

(Image)
Pre-exponential factors for the forward and backward reactions are $10^{15} \mathrm{~s}^{-1}$ and $10^{11} \mathrm{~s}^{-1}$, respectively. If the value of $\log \mathrm{K}$ for the reaction at $500 \mathrm{~K}$ is $6$ , the value of $\left|\log \mathrm{k}_{\mathrm{b}}\right|$ at $250 \mathrm{~K}$ is $\qquad$
$[\mathrm{K}=$ equilibrium constant of the reaction
$\mathrm{k}_{\mathrm{f}}=$ rate constant of forward reaction
$\mathrm{k}_{\mathrm{b}}=$ rate constant of backward reaction]