State the Avogadro law of ideal gas

Explanation

### Step-by-Step Solution:

1. **Understanding the Concept**: Avogadro's law relates to the behavior of gases and states that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules.

2. **State the Law**: The formal statement of Avogadro's law is:
- "Equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules."

3. **Implications of the Law**:
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