Assertion (A) : The order of the reaction,
`CH_(3)COOC_(2)H_(5) + H_(2)O hArr CH_(3)COOH + C_(2)H_(5)OH`
is `2`. Reason (R ): The molecularity of this reaction is `2`.

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 solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understanding the Reaction
The reaction given is:
\[ CH_3COOC_2H_5 + H_2O \rightleftharpoons CH_3COOH + C_2H_5OH \]
This is a hydrolysis reaction where an ester reacts with water to form an acid and an alcohol.

### Step 2: Determining the Order of the Reaction
The order of a reaction is determined by how the rate of the reaction depends on the concentration of the reactants. In this case, since water is present in excess, its concentration remains relatively constant throughout the reaction. Therefore, the rate of the reaction primarily depends on the concentration of the ester \( CH_3COOC_2H_5 \).

Given that the rate of reaction can be expressed as:
\[ \text{Rate} = k [CH_3COOC_2H_5] \]
This indicates that the reaction behaves as a first-order reaction with respect to the ester. Thus, the overall order of the reaction is 1, not 2.

### Step 3: Understanding Molecularity
Molecularity refers to the number of reactant particles that collide to form products in a single step of a reaction. In this case, there are two reactants involved:
1. \( CH_3COOC_2H_5 \) (the ester)
2. \( H_2O \) (water)

Since both of these reactants are involved in the rate-determining step, the molecularity of the reaction is:
\[ 1 + 1 = 2 \]

### Conclusion
- Assertion (A): The order of the reaction is 2. **(Incorrect)**
- Reason (R): The molecularity of this reaction is 2. **(Correct)**

Thus, the correct conclusion is that the assertion is incorrect, while the reason is correct.

### Final Answer
The correct option is that Assertion (A) is incorrect and Reason (R) is correct.

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