Assertion : Phenol undergoes Kolbe's reaction whereas ethanol does not .
Reason : Phenoxide ion is more basic than ethoxide ion .

Options

A. If both the assertion and reason are true statement and reason is correct explanation of the assertion .
B. If both the assertion and reason are true statement but reason is not a correct explanation of the assertion .
C. If the assertion is true but the reason is a false statement.
D. If both assertion and reason are false statements.

Explanation

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

### Step 1: Understanding the Assertion
The assertion states that "Phenol undergoes Kolbe's reaction whereas ethanol does not."

**Explanation:**
- Kolbe's electrolysis involves the decarboxylation of carboxylic acids or their salts. In this case, phenol can be converted to phenoxide ion when reacted with a base like NaOH. The phenoxide ion can then react with CO2 in the Kolbe's reaction to form salicylic acid.
- Ethanol, on the other hand, does not undergo Kolbe's reaction because the ethoxide ion (the deprotonated form of ethanol) cannot effectively react with CO2 in the same way.

### Step 2: Understanding the Reason
The reason states that "Phenoxide ion is more basic than ethoxide ion."

**Explanation:**
- Basicity refers to the ability of a species to accept protons (H+). The phenoxide ion has its negative charge delocalized over the aromatic ring due to resonance, making it less basic. In contrast, the ethoxide ion has a localized negative charge, which makes it more basic and more likely to accept a proton.

### Step 3: Analyzing the Truth of Assertion and Reason
- The assertion is **true**: Phenol does undergo Kolbe's reaction, while ethanol does not.
- The reason is **false**: Phenoxide ion is not more basic than ethoxide ion; in fact, ethoxide ion is more basic.

### Conclusion
Since the assertion is true and the reason is false, the correct option is that the assertion is true but the reason is false.

### Final Answer
The correct option is C: "Assertion is true but reason is false."

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