Name the gas evolved in each of the following cases
Action of strong heat on potassium nitrate

Explanation

To determine the gases evolved when potassium nitrate (KNO3) is heated, we can follow these steps:

### Step 1: Identify the chemical reaction
When potassium nitrate is subjected to strong heat, it decomposes. The chemical equation for this reaction can be represented as:
\[ 2 \text{KNO}_3 (s) \rightarrow \text{K}_2\text{O} (s) + \text{N}_2 (g) + 2 \text{O}_2 (g) \]

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