Can you concentrate nitric acid beyond 68% by boiling, if not then how is it concentrated ?

Explanation

### Step-by-Step Solution:

1. **Understanding the Concentration of Nitric Acid**:
- Nitric acid (HNO3) can be found in various concentrations, with 68% being a common concentration for commercial nitric acid.

2. **Boiling and Azeotropes**:
- When boiling nitric acid, it reaches a point where it forms an azeotrope at 68%. An azeotrope is a mixture that has a constant boiling point and composition, meaning that as it boils, the ratio of the components does not change.

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