If butane on combustion gives carbon monoxide. Find the number of `O_(2)` molecule required

Options

A. 6
B. 5.5
C. 4.5
D. 4

Answer

To solve the problem of how many O₂ molecules are required for the combustion of butane (C₄H₁₀) that produces carbon monoxide (CO), we can follow these steps:

### Step 1: Write the balanced chemical equation for the combustion of butane.
The general form of the combustion reaction of butane is:
\[ \text{C}_4\text{H}_{10} + \text{O}_2 \rightarrow \text{CO} + \text{H}_2\text{O} \]

However, since we are specifically looking at the combustion producing carbon monoxide instead of carbon dioxide, we will write the equation accordingly.

### Step 2: Determine the products of the reaction.
When butane combusts in a limited supply of oxygen, it produces carbon monoxide and water:
\[ \text{C}_4\text{H}_{10} + \text{O}_2 \rightarrow 4\text{CO} + 5\text{H}_2\text{O} \]

### Step 3: Balance the equation.
Now we need to balance the equation. For every 1 molecule of butane, we need to determine how many O₂ molecules are required.

1. From the products, we see that 4 moles of CO are produced.
2. Each CO molecule requires 0.5 O₂ to form. Therefore, for 4 CO:
\[ 4 \text{CO} \rightarrow 4 \times 0.5 \text{O}_2 = 2 \text{O}_2 \]

3. Additionally, we need to balance the water (H₂O) produced. Since 5 moles of H₂O are produced, we need:
\[ 5 \text{H}_2\text{O} \rightarrow 5 \times 0.5 \text{O}_2 = 2.5 \text{O}_2 \]

### Step 4: Combine the oxygen requirements.
Now we add the oxygen requirements from both products:
- From CO: 2 O₂
- From H₂O: 2.5 O₂

Total O₂ required:
\[ 2 + 2.5 = 4.5 \text{O}_2 \]

### Step 5: Write the final balanced equation.
Thus, the balanced equation for the combustion of butane producing carbon monoxide is:
\[ \text{C}_4\text{H}_{10} + 4.5 \text{O}_2 \rightarrow 4 \text{CO} + 5 \text{H}_2\text{O} \]

### Conclusion:
The number of O₂ molecules required for the combustion of butane to produce carbon monoxide is 4.5 O₂ molecules.

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