Question

Assertion: The order of a reaction is sometimes altered by conditions.
Reason: Hydrolysis of ester is a pseudo first order reaction when water is taken in large excess.​

Answer 1

Answer:

assertion nd reasin is true but assertion is not correct exlpanation of reason

Answer 2

Both the reason and assertion are correct. But the reason does not explain the correctness of the aasertion.

Explanation:

• The rate of a reaction is affected by a number of factors like nature of reaction, the concentration of the reactants, and the reactant pressure.
• The order of the reaction gets affected by the presence of an excess specie in the reactant side.
• In the hydrolysis of the ester, the reaction is a second order reaction, but when the water is present in excess, it becomes first order, and hence called the pseudo first order reaction.
• The rate of reaction can be written as:

        $Rate=k^{'} [CH_{3} COOC_{2}H_{5}][H_{2}O]$

         $Rate=k [CH_{3} COOC_{2}H_{5}]$  when water is in excess.

• Thus both assertion and reason are correct, but reason does not explain the correctness of assertion.