The compound which is not formed when a mixture of n-butyl bromide and ethyl bromide treated with sodium metal in the presence of dry ether is

Options

A. Butane
B. Octane
C. Hexane
D. Ethane

Answer

To solve the problem of determining which compound is not formed when a mixture of n-butyl bromide and ethyl bromide is treated with sodium metal in the presence of dry ether, we can follow these steps:

### Step 1: Understand the Reaction
When alkyl halides are treated with sodium in the presence of dry ether, a reaction known as the Wurtz reaction occurs. This reaction typically leads to the formation of alkanes and sodium halides.

### Step 2: Identify the Reactants
In this case, we have two alkyl bromides:
- n-butyl bromide (C4H9Br)
- ethyl bromide (C2H5Br)

### Step 3: Possible Products from Wurtz Reaction
1. **Using two moles of n-butyl bromide:**
- \( 2 \, \text{C}_4\text{H}_9\text{Br} + 2 \, \text{Na} \rightarrow \text{C}_8\text{H}_{18} + 2 \, \text{NaBr} \)
- This produces **n-octane (C8H18)**.

2. **Using two moles of ethyl bromide:**
- \( 2 \, \text{C}_2\text{H}_5\text{Br} + 2 \, \text{Na} \rightarrow \text{C}_4\text{H}_{10} + 2 \, \text{NaBr} \)
- This produces **butane (C4H10)**.

3. **Using one mole of n-butyl bromide and one mole of ethyl bromide:**
- \( \text{C}_4\text{H}_9\text{Br} + \text{C}_2\text{H}_5\text{Br} + 2 \, \text{Na} \rightarrow \text{C}_6\text{H}_{14} + 2 \, \text{NaBr} \)
- This produces **n-hexane (C6H14)**.

### Step 4: List the Products
From the above reactions, the possible products formed are:
- n-octane (C8H18)
- butane (C4H10)
- n-hexane (C6H14)

### Step 5: Identify the Compound Not Formed
The question asks for the compound that is **not formed**. The products we have identified do not include:
- **Ethane (C2H6)**

### Conclusion
Thus, the compound which is not formed when a mixture of n-butyl bromide and ethyl bromide is treated with sodium metal in the presence of dry ether is **ethane (C2H6)**.