Assertion (A): Hydrolyiss of ethyl acetate in the presence of acid is a reaction of first order whereas in the presence of alkali, it is a reaction of second order.
Reason (R ): Acid acts as catalyst only whereas alkali act as one of the reactant.

Options

A. If both `(A)` and `(R )` are correct, and `(R )` is the correct explnation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is noth the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If `(A)` is incorrect, but `(R )` is correct.

Explanation

To analyze the assertion and reason provided in the question, let's break down the information step by step.

### Step 1: Understanding Hydrolysis of Ethyl Acetate
Hydrolysis of ethyl acetate (CH3COC2H5) involves the reaction of ethyl acetate with water to form acetic acid and ethanol. The reaction can occur in the presence of either an acid or an alkali.

### Step 2: Hydrolysis in the Presence of Acid
When ethyl acetate is hydrolyzed in the presence of an acid, the reaction behaves as a pseudo-first-order reaction. This is because the concentration of water is much higher than that of ethyl acetate, making the reaction rate dependent primarily on the concentration of ethyl acetate. Therefore, the order of the reaction is first with respect to ethyl acetate.

### Step 3: Hydrolysis in the Presence of Alkali
In contrast, when the hydrolysis occurs in the presence of an alkali (like NaOH), the reaction is second order. This is because both the ethyl acetate and the hydroxide ions from the alkali are involved in the rate-determining step of the reaction. Hence, the reaction depends on the concentrations of both reactants.

### Step 4: Analyzing the Assertion and Reason
- **Assertion (A)**: The statement that hydrolysis of ethyl acetate in the presence of acid is a first-order reaction, while in the presence of alkali it is a second-order reaction, is correct.
- **Reason (R)**: The reason states that acid acts as a catalyst, while alkali acts as one of the reactants. This is also correct because the acid speeds up the reaction without being consumed, whereas the alkali is consumed in the reaction.

### Conclusion
Both the assertion and reason are correct, and the reason correctly explains the assertion.

### Final Answer
Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.

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