The stronger base is

Options

A. `CH_(3)CH_(2)^(-)`
B. `CH_(2)=CH^(-)`
C. `CH-=C^(-)`
D. `Cl^(-)`

Answer

To determine the stronger base among the given options, we need to analyze the stability of the negative charges present in each option. A stronger base is characterized by a less stable negative charge, which means it is more likely to accept a proton (H+).

**Step-by-Step Solution:**

1. **Understanding Bases**: A base is defined as a substance that can accept a proton (H+). For a species to act as a base, it must have a negative charge or a lone pair of electrons.

2. **Identifying the Options**: The options provided are:
- Option A: CH3CH2⁻ (Ethyl anion)
- Option B: CH2CNH (Cyanomethyl anion)
- Option C: C≡C⁻ (Acetylide anion)
- Option D: Cl⁻ (Chloride ion)

3. **Analyzing Stability of Negative Charges**:
- **Option A (CH3CH2⁻)**: The negative charge is on an sp³ hybridized carbon. This carbon is less electronegative and the negative charge is less stable.
- **Option B (CH2CNH)**: The negative charge is on a carbon that is adjacent to a cyano group (C≡N), which can stabilize the negative charge through resonance. This makes it more stable than option A.
- **Option C (C≡C⁻)**: The negative charge is on a carbon that is sp hybridized. This carbon is more electronegative, making the negative charge more stable.
- **Option D (Cl⁻)**: Chlorine is a highly electronegative atom and holds the negative charge very stably due to its high electronegativity.

4. **Comparing Stability**:
- The stability order of the negative charges from least stable to most stable is:
- Option A (CH3CH2⁻) < Option B (CH2CNH) < Option C (C≡C⁻) < Option D (Cl⁻)
- Therefore, the least stable negative charge is in Option A (CH3CH2⁻).

5. **Conclusion**: Since the stronger base corresponds to the least stable negative charge, the strongest base among the options is **Option A (CH3CH2⁻)**.

**Final Answer**: The stronger base is **Option A (CH3CH2⁻)**.

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