Write balanced chemical equation of the reaction for the preparation of nitric acid in the laboratory. What type of change is observed if the reaction mixture is heated above `200^@C`? 

Explanation

To answer the question about the preparation of nitric acid in the laboratory and the effects of heating the reaction mixture above 200°C, we can break it down into two parts: writing the balanced chemical equation and discussing the changes observed at elevated temperatures.

### Step 1: Write the Balanced Chemical Equation

The preparation of nitric acid (HNO₃) in the laboratory can be done using potassium nitrate (KNO₃) and sulfuric acid (H₂SO₄). The balanced chemical equation for this reaction is:

\[ \text{KNO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{KHSO}_4 + \text{HNO}_3 \]

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