Assertion (A) Sodium chloride is added to precipitate soap after saponification.
Reason (R) Hydrolysis of esters of long chain fatty acids by alkali produces soap in colloidal form.

Options

A. Assertion and reason both are correct statements but reason does not explain assertion.
B. Assertion and reason both are correct and reason explains the assertion.
C. Both assertion and reason are wrong statements.
D. Assertion is correct statement reason is wrong statement.

Explanation

To analyze the given assertion and reason, we will break down the information step by step.

### Step 1: Understand the Assertion
The assertion states that "Sodium chloride is added to precipitate soap after saponification."

- **Explanation**: Saponification is the process of hydrolyzing fats or oils (which are esters of long-chain fatty acids) in the presence of an alkali (like sodium hydroxide). After this reaction, soap is formed, which is often in a colloidal form. To help in the precipitation of soap from this colloidal solution, sodium chloride (common salt) is added. The addition of salt helps to reduce the solubility of soap in water, thus facilitating its precipitation.

### Step 2: Understand the Reason
The reason states that "Hydrolysis of esters of long chain fatty acids by alkali produces soap in colloidal form."

- **Explanation**: This statement is true. When esters (like fats) are hydrolyzed by an alkali, they break down into glycerol and fatty acid salts, which are the soap. The soap produced is typically in a colloidal form due to its long hydrocarbon chains, which makes it less soluble in water.

### Step 3: Determine the Correctness of Both Statements
- **Assertion**: Correct. Sodium chloride is indeed added to precipitate soap after saponification.
- **Reason**: Correct. Hydrolysis of esters of long-chain fatty acids by alkali does produce soap in colloidal form.

### Step 4: Establish the Relationship
- The reason provided explains why the assertion is true. The hydrolysis of esters leads to the formation of soap, and the addition of sodium chloride helps in the precipitation of that soap.

### Conclusion
Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.

### Final Answer:
- **Assertion (A)**: True
- **Reason (R)**: True
- **Relationship**: R is the correct explanation of A.

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