Iodoform test is not given by

Options

A. `CH_(3)COCH_(3)`
B. `CH_(3)COC_(2)H_(5)`
C. `C_(6)H_(5)COCH_(3)`
D. `C_6H_5COC_(6)H_(5)`

Answer

To determine which compound does not give the Iodoform test, we need to understand the criteria for a compound to undergo this test. The Iodoform test is specifically used to identify the presence of methyl ketones or methyl aldehydes.

### Step-by-Step Solution:

1. **Understanding the Iodoform Test**:
- The Iodoform test is used to detect methyl ketones (RCOCH3) or methyl aldehydes (RCHO) that have a methyl group adjacent to the carbonyl group.

2. **Analyzing the Options**:
- We need to analyze each option to see if they contain a methyl group directly attached to a carbonyl group.

3. **Option A: CH3COCH3 (Acetone)**:
- This is a methyl ketone (specifically, acetone). It has the structure CH3C(=O)CH3, which clearly shows a methyl group adjacent to the carbonyl group.
- **Conclusion**: This compound will give a positive Iodoform test.

4. **Option B: CH3COC2H5 (Ethyl Methyl Ketone)**:
- This compound has the structure CH3C(=O)C2H5. Here, the carbonyl group is attached to an ethyl group (C2H5) instead of a methyl group.
- **Conclusion**: This compound will not give a positive Iodoform test.

5. **Option C: C6H5COCH3 (Acetophenone)**:
- This compound has the structure C6H5C(=O)CH3. It has a methyl group adjacent to the carbonyl group.
- **Conclusion**: This compound will give a positive Iodoform test.

6. **Option D: C6H5COC6H5 (Benzophenone)**:
- This compound has the structure C6H5C(=O)C6H5. There are no methyl groups adjacent to the carbonyl group.
- **Conclusion**: This compound will not give a positive Iodoform test.

7. **Final Conclusion**:
- The compound that does not give the Iodoform test is **Option B: CH3COC2H5 (Ethyl Methyl Ketone)**.

### Summary:
The correct answer is **Option B**.