Name the gas evolved in each of the following cases :
Nitrogen combines with hydrogen.

Explanation

To solve the question "Name the gas evolved when nitrogen combines with hydrogen," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this case are nitrogen (N₂) and hydrogen (H₂).

2. **Understand the Reaction**: When nitrogen and hydrogen combine, they undergo a chemical reaction to form ammonia (NH₃). This reaction typically occurs under specific conditions, such as high temperature (around 773 Kelvin) and pressure.

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