Which of the following compounds does not show electromeric effect

Options

A. `CH_(3)-CN`
B. `CH_(3)-CHO`
C. `CH_(2)=CH_(2)`
D. `CH_(3)-Cl`

Answer

To determine which of the following compounds does not show the electromeric effect, we will analyze each compound based on the definition of the electromeric effect. The electromeric effect involves the temporary displacement of electrons within a molecule due to the presence of an electronegative atom, resulting in the formation of a dipole.

### Step-by-step Solution:

1. **Understanding Electromeric Effect**:
- The electromeric effect occurs when electrons are displaced within a molecule due to the influence of an electronegative atom, leading to the development of partial positive and negative charges.

2. **Analyzing Option 1: CH3CN (Acetonitrile)**:
- In CH3CN, the nitrogen atom is more electronegative than carbon.
- The electron cloud shifts towards nitrogen, resulting in a negative charge on nitrogen and a positive charge on the adjacent carbon.
- **Conclusion**: CH3CN shows the electromeric effect.

3. **Analyzing Option 2: CH3COOH (Acetic Acid)**:
- In CH3COOH, the oxygen atom is more electronegative than carbon.
- The electron cloud shifts towards oxygen, creating a negative charge on oxygen and a positive charge on the adjacent carbon.
- **Conclusion**: CH3COOH shows the electromeric effect.

4. **Analyzing Option 3: Ethene (C2H4)**:
- In ethene, there is a double bond between the two carbon atoms.
- The presence of the double bond allows for the delocalization of electrons. When an electrophile approaches, electrons can be displaced, leading to the formation of charges.
- **Conclusion**: Ethene shows the electromeric effect.

5. **Analyzing Option 4: CH3Cl (Methyl Chloride)**:
- In CH3Cl, chlorine is more electronegative than carbon.
- However, the interaction here leads to a dipole moment (partial charges) rather than a permanent charge separation. The electron cloud is not displaced in a way that leads to a permanent charge distribution.
- **Conclusion**: CH3Cl does not show the electromeric effect.

### Final Answer:
The compound that does not show the electromeric effect is **CH3Cl (Methyl Chloride)**.

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