Write balanced chemical equations for the following reactions of:
The preparation of hydrogen chloride from sodium chloride and sulphuric acid. State whether the sulphuric acid should be concentrated or dilute.

Explanation

To write the balanced chemical equation for the preparation of hydrogen chloride (HCl) from sodium chloride (NaCl) and sulfuric acid (H2SO4), we follow these steps:

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

### Step 2: Determine the Type of Sulfuric Acid
It is important to note that concentrated sulfuric acid is used in this reaction. This is because concentrated sulfuric acid acts as a dehydrating agent, which helps to prevent the formation of water that could lead to the production of toxic fumes of HCl.

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