Question

The hydrolysis of ethyl acetate,
$C{H}_{3}COO{C}_2{H}_5+H_{2}O\stackrel{H^{+}}{\to }C{H}_{3}COOH+C_2{H}_{5}OH$ is a reaction of:

• A. zero order
• B. pseudo first order
• C. second order
• D. third order

Answer 1

The correct option is B pseudo first order

A reaction which is not the first-order reaction naturally but made the first order by increasing or decreasing the concentration of one or the other reactant is known as Pseudo first-order reaction.

Hydrolysis of ethyl acetate in presence of an excess of water:

$C{H}_{3}COO{C}_2{H}_5+H_{2}O\left(\text{excess}\right)\stackrel{H+}{\to }C{H}_{3}COOH+C_2{H}_{5}OH$

$r=k\left[C{H}_{3}COO{C}_2{H}_5{]}^2\right[H_{2}O{]}^0$

Excess $\left[H_{2}O\right]$ can cause the independency of reaction on $H_{2}O$.

Hence, it is a pseudo-first-order reaction.

Hence, the correct answer is option $\text{B}$.