From which of the following can ethane be prepared in one step?

Options

A. Methyl lodine
B. Sodium propanoate
C. Ethyl magnesium bromide
D. All of these

Explanation

To determine from which of the given compounds ethane can be prepared in one step, let’s analyze each option systematically.

### Step 1: Analyze Methyl Iodide (CH3I)
- **Reaction**: Methyl iodide can react with sodium in the presence of dry ether.
- **Equation**:
\[ 2 \, \text{CH}_3\text{I} + 2 \, \text{Na} \rightarrow \text{C}_2\text{H}_6 + 2 \, \text{NaI} \]
- **Product**: The reaction produces ethane (C2H6) and sodium iodide (NaI).
- **Conclusion**: Ethane can be prepared from methyl iodide in one step.

### Step 2: Analyze Sodium Propionate (C2H5COONa)
- **Reaction**: Sodium propionate reacts with a strong base (NaOH) in the presence of calcium oxide (CaO).
- **Equation**:
\[ \text{C}_2\text{H}_5\text{COONa} + \text{NaOH} \xrightarrow{\text{CaO}} \text{C}_2\text{H}_6 + \text{Na}_2\text{CO}_3 \]
- **Product**: The reaction produces ethane (C2H6) and sodium carbonate (Na2CO3).
- **Conclusion**: Ethane can also be prepared from sodium propionate in one step.

### Step 3: Analyze Ethyl Magnesium Bromide (C2H5MgBr)
- **Reaction**: Ethyl magnesium bromide reacts with water (H2O).
- **Equation**:
\[ \text{C}_2\text{H}_5\text{MgBr} + \text{H}_2\text{O} \rightarrow \text{C}_2\text{H}_6 + \text{MgBr(OH)} \]
- **Product**: The reaction produces ethane (C2H6) and magnesium bromide hydroxide (MgBr(OH)).
- **Conclusion**: Ethane can also be prepared from ethyl magnesium bromide in one step.

### Final Conclusion
Since ethane can be prepared from all three compounds (methyl iodide, sodium propionate, and ethyl magnesium bromide) in one step, the correct answer is:
**Option 4: All of these.**

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