Question

The mechanism of the reaction: $N{u}^{-}+R-X\to R-Nu+X^{-}$ is:
$N{u}^{-}+R-X\to$ [Transition state] (slow) [Transition state] $\to Nu-R+X^{-}$ (fast) The rate of reaction can be increased by:

• A. increasing the cone, of $N{u}^{-}$ only
• B. increasing the core, of $R-X$ only
• C. increasing the cone, of both $N{u}^{-}$ and $R-X$
• D. decreasing the cone, of both $N{u}^{-}$ and $R-X$

Answer 1

Answer: (A)

increasing the cone, of $N{u}^{-}$ only

Since the first step is slow , step (I) is the rate determining step and the reaction depends of $N{u}^{-}$ and $R-X$

$N{u}^{-}+R-X\to$ transformation step

So, rate can be increased by increased by increasing conc. Of $N{u}^{-}$ only.