Question

The first steps of $S{N}^1$ and $S{N}^2$ reactions are, respectively

• A. Both exothermic
• B. Both endothermic
• C. Endothermic and exothermic
• D. Exothermic and endothermic

Answer 1

Answer: (C)

In $S{N}^2$, there is only one step, and it is exothermic. But in $S{N}^1$ there are two steps first step; is endothermic and second step is exothermic