Question

The value of rate of a pseudo first order reaction depends upon:

• A. the concentration of both the reactants present in the reaction
• B. the concentration of the reactant present in small amount
• C. the concentration of the reactant present in excess
• D. the value of $\Delta H$ of the reaction

Answer 1

Answer: (B)

the concentration of the reactant present in small amount

$C{H}_{3}COO{C}_2{H}_5+H_{2}O\to C{H}_{3}COOH+C{H}_{3}OH$
0.01 10 0 0

0 9.99 0.01 0.01
The above reaction is a Pseudo first order reaction. As it can be seen from the above reaction that the concentration of water is not changing much. Thus the rate of the reaction is not much affacted by the change in concentration of water. However rate of the reaction get significantly affacted by the concentration gradient of ethyl acetate. Hence, the rate of Pseudo first order reaction depends upon the concentration of the reactant present in small amount.
Option B is correct.