Hydrogen gas has high calorific value but it is not used as a domestic fuel. Why ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Calorific Value**:
- Hydrogen gas has a high calorific value, meaning it releases a large amount of energy when burned. This characteristic makes it a potential candidate for fuel.

2. **Combustibility**:
- Hydrogen is a highly combustible gas. This means it can ignite easily and burn rapidly. However, this property also poses a risk, as the combustion of hydrogen cannot be easily controlled.

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