Which of the following organic compound is used as a fuel?

Options

A. `HCOOH`
B. `C_4H_10`
C. `CH_3OH`
D. `CHCOOH`

Explanation

To determine which of the following organic compounds is used as a fuel, we can follow these steps:

### Step 1: Identify the Organic Compounds
We need to look at the list of organic compounds provided in the question. For this solution, let's assume the organic compounds listed are:
1. Butane (C4H10)
2. Acetic acid (C2H4O2)
3. Ethanol (C2H5OH)
4. Propanoic acid (C3H6O2)

### Step 2: Understand the Characteristics of Fuels
Fuels are typically hydrocarbons or compounds that can release energy when burned. Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon. When burned in the presence of oxygen, they produce carbon dioxide (CO2), water (H2O), and energy (heat).

### Step 3: Analyze Each Compound
- **Butane (C4H10)**: This is a hydrocarbon. When burned, it produces CO2, H2O, and heat. It is commonly used as a fuel in LPG (Liquefied Petroleum Gas).
- **Acetic acid (C2H4O2)**: This is a carboxylic acid and not a hydrocarbon. It is not typically used as a fuel.
- **Ethanol (C2H5OH)**: This is an alcohol and can be used as a fuel, but it is not a hydrocarbon in the strictest sense.
- **Propanoic acid (C3H6O2)**: This is also a carboxylic acid and not a hydrocarbon. It is not used as a fuel.

### Step 4: Conclusion
From the analysis, the compound that can be used as a fuel is **Butane (C4H10)**. It is a hydrocarbon that burns efficiently to produce energy.

### Final Answer
**Butane (C4H10)** is the organic compound used as a fuel.

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