Consider a mixture ' X ' which is made by dissolving 0.4 mol of $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{SO}_4\right] \mathrm{Br}$ and 0.4 mol of $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{Br}\right] \mathrm{SO}_4$ in water to make 4 L of solution. When 2 L of mixture ' X ' is allowed to react with excess of $\mathrm{AgNO}_3$, it forms precipitate ' Y '. The rest 2 L of mixture ' X ' reacts with excess $\mathrm{BaCl}_2$ to form precipitate ' Z '. Which of the following statements is CORRECT?

$$ \text { Consider the following two reactions } \mathrm{A} \text { and } \mathrm{B} \text {. } $$

Numerical value of [molar mass of $x+$ molar mass of $y$ ] is $\_\_\_\_$

$$ \text { Arrange the following carbanions in the decreasing order of stability. } $$

Choose the correct answer from the options given below :

At $27^{\circ} \mathrm{C}$ in presence of a catalyst, activation energy of a reaction is lowered by $10 \mathrm{~kJ} \mathrm{~mol}^{-1}$. The logarithm of ratio of $\frac{\mathrm{k} \text { (catalysed) }}{\mathrm{k} \text { (uncatalysed) }}$ is….

(Consider that the frequency factor for both the reactions is same)