Which has the highest calorific value?

Options

A. Kerosene
B. Biogas
C. Ethanol
D. Butane

Explanation

To determine which substance has the highest calorific value among kerosene, biogas, ethanol, and butane, we will compare their calorific values as follows:

### Step 1: Identify the calorific values of each substance
- **Kerosene**: 13,000 kcal/kg
- **Biogas**: 5,000 kcal/kg
- **Ethanol**: 29,700 kcal/kg
- **Butane**: 11,950 kcal/kg

### Step 2: List the calorific values in order
1. Ethanol: 29,700 kcal/kg
2. Kerosene: 13,000 kcal/kg
3. Butane: 11,950 kcal/kg
4. Biogas: 5,000 kcal/kg

### Step 3: Compare the values
From the list, we can see that ethanol has the highest calorific value at 29,700 kcal/kg, followed by kerosene, butane, and biogas.

### Conclusion
The substance with the highest calorific value is **Ethanol**.

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