Which of the following is the strongest base ?

Options

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

Answer

To determine which of the given compounds is the strongest base, we can follow these steps:

### Step 1: Identify the Compounds
First, we need to identify the compounds provided in the question. Let's assume the compounds are:
1. Ethane (C2H6)
2. Acetylene (C2H2)
3. Propane (C3H8)
4. Butyne (C4H6)

### Step 2: Understand Acid-Base Relationships
Recall that the strength of a base is inversely related to the strength of its conjugate acid. A strong acid has a weak conjugate base, while a weak acid has a strong conjugate base.

### Step 3: Analyze Each Compound
- **Ethane (C2H6)**: Ethane is a weak acid. Therefore, its conjugate base (C2H5-) will be relatively strong.

- **Acetylene (C2H2)**: Acetylene is a strong acid. Its conjugate base (C2H-) will be weak.

- **Propane (C3H8)**: Similar to ethane, propane is also a weak acid, and its conjugate base (C3H7-) will be strong.

- **Butyne (C4H6)**: Butyne is a stronger acid than ethane and propane, so its conjugate base will be weaker.

### Step 4: Compare the Conjugate Bases
From the analysis:
- Ethane (C2H5-) and Propane (C3H7-) have strong conjugate bases.
- Acetylene (C2H-) and Butyne have weak conjugate bases.

### Step 5: Determine the Strongest Base
Since ethane and propane have strong conjugate bases, we compare their strengths. Ethane's conjugate base (C2H5-) is stronger than that of butyne, making it the strongest base among the options provided.

### Conclusion
Thus, the strongest base among the given compounds is **Ethane (C2H6)**.