What happens when (write balanced chemical equations only)
Concentrated sulphuric acid is added to sodium chloride.

Explanation

To solve the question regarding the reaction of concentrated sulfuric acid with sodium chloride, we will write the balanced chemical equations for both scenarios: when the reaction occurs below 200 degrees Celsius and when it occurs above 200 degrees Celsius.

### Step-by-Step Solution:

1. **Identify the Reactants:**
- The reactants in this reaction are concentrated sulfuric acid (H₂SO₄) and sodium chloride (NaCl).

2. **Reaction Below 200 Degrees Celsius:**
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