In order to produce pure dihydrogen gas, which combination is used?

Explanation

To produce pure dihydrogen gas (H2), we can use the following combinations:

### Step-by-Step Solution:

1. **Identify the Reactants**:
To produce dihydrogen gas, we can use metals such as magnesium (Mg) or aluminum (Al) in combination with acids or bases.

2. **First Combination - Magnesium and Sulfuric Acid**:
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