When most of the metals are treated with nitric acid they do not produce hydrogen gas. Why?

Explanation

### Step-by-Step Solution:

1. **Understanding the Reaction**: When metals react with nitric acid (HNO3), we expect hydrogen gas (H2) to be produced, as is common with other acids. However, this is not the case with nitric acid.

2. **Nature of Nitric Acid**: Nitric acid is a strong oxidizing agent. This means that it has the ability to accept electrons from other substances and can cause oxidation.

3. **Oxidation Process**: In the presence of nitric acid, instead of producing hydrogen gas, the nitric acid oxidizes the hydrogen ions (H+) that would typically combine to form H2. Instead, it donates oxygen to the reaction.

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