Which one of the following has the highest calorific value ?

Options

A. `CH_(4)`
B. LPG
C. Coal gas
D. `H_(2)`

Answer

To determine which of the given options has the highest calorific value, we will analyze the calorific values of each substance listed in the question.

### Step-by-Step Solution:

1. **Understand Calorific Value**:
- Calorific value is defined as the amount of heat energy produced when a substance is completely burned. It is usually expressed in kilocalories per kilogram (kcal/kg).

2. **List the Options**:
- The options provided are:
- A) Methane (CH₄)
- B) LPG (Liquefied Petroleum Gas)
- C) Coal Gas
- D) Hydrogen (H₂)

3. **Find Calorific Values**:
- Now, we will look at the calorific values of each option:
- **Methane (CH₄)**: The calorific value is approximately **13,289 kcal/kg**.
- **LPG**: The calorific value is approximately **11,000 kcal/kg**.
- **Coal Gas**: The calorific value is approximately **8,126 kcal/kg**.
- **Hydrogen (H₂)**: The calorific value is approximately **33,000 kcal/kg**.

4. **Compare the Calorific Values**:
- Now, we compare the calorific values we found:
- Methane: 13,289 kcal/kg
- LPG: 11,000 kcal/kg
- Coal Gas: 8,126 kcal/kg
- Hydrogen: 33,000 kcal/kg

5. **Identify the Highest Calorific Value**:
- From the comparison, we can see that **Hydrogen (H₂)** has the highest calorific value of **33,000 kcal/kg**.

6. **Conclusion**:
- Therefore, the substance with the highest calorific value among the options provided is **D) Hydrogen**.