Question

1 L of 2 M CH3COOH is mixed with 1 L of 3M C2H5OH to form an ester. The rate of the reaction with respect to the initial rate when each solution is diluted with an equal volume of water will be

• A. 0.5 times
• B. 4 times
• C. 0.25 times
• D. 2 times

Answer 1

Answer: (B)

4 times

Answer 2

Esterification is a second order reaction
$CH_{3}COOH+C_{2}H_{5}OH \to CH_{3}COOC_{2}H_{5}+H_{2}O$
$r=k\left[CH_{3}COOH\right]\left[C_{2}H_{5}OH\right]$
$Order = 2$
When equal volume of two solutions are mixed, concentration of the solutions reduces to half the initial value. Hence, rate of reaction gets reduced to $\frac{1}{4}$ initial rate.