Assertion (A) : The C-O-C bond angle in thers is slightly less than tetrahedral angle.
Reason (R ) : Due to the repulsive interaction between the two alkyl groups in ethers

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is NOT the corrrect explanation of A
C. A is true but R is false
D. A is false and R is True

Explanation

To solve the question regarding the assertion and reason related to the C-O-C bond angle in ethers, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the C-O-C bond angle in ethers is slightly less than the tetrahedral angle (which is approximately 109.5°).
- In ethers, the general structure is R-O-R', where R and R' are alkyl groups.

2. **Analyzing the Bond Angle**:
- In a perfect tetrahedral geometry, the bond angles are 109.5°.
- However, in ethers, due to the presence of two alkyl groups, the bond angle may be affected.

3. **Understanding the Reason (R)**:
- The reason provided states that the bond angle is affected due to repulsive interactions between the two alkyl groups in ethers.
- Alkyl groups are electron-donating and can create steric hindrance, which leads to repulsion.

4. **Hybridization**:
- The oxygen atom in ethers is sp³ hybridized, which typically suggests a tetrahedral arrangement.
- This hybridization results in two lone pairs and two sigma bonds, leading to a bond angle that is influenced by the repulsion between the alkyl groups.

5. **Conclusion**:
- Since the assertion mentions that the C-O-C bond angle is slightly less than the tetrahedral angle, and the reason correctly explains that this is due to repulsive interactions between the alkyl groups, both statements are true.
- Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both assertion (A) and reason (R) are true, and the reason is the correct explanation of the assertion.

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