Equal volumes of all gases under same temperature and pressure contain equal number of molecules according to

Options

A. Avogadro's law
B. Charle's law
C. Boyle's law
D. Graham's law

Explanation

To solve the question "Equal volumes of all gases under the same temperature and pressure contain equal number of molecules according to," we need to identify the correct law that describes this relationship.

### Step-by-Step Solution:

1. **Understanding the Question**:
The question states that equal volumes of gases at the same temperature and pressure contain an equal number of molecules. We need to find which gas law supports this statement.

**Hint**: Consider the definitions and implications of the gas laws mentioned.

2. **Identifying the Relevant Gas Laws**:
The options provided are:
- Avogadro's Law
- Charles' Law
- Boyle's Law
- Graham's Law

**Hint**: Recall the main principles of each gas law to see which one relates to the volume and number of molecules.

3. **Reviewing Avogadro's Law**:
Avogadro's Law states that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules. This directly supports the statement in the question.

**Hint**: Think about what Avogadro's Law specifically mentions regarding volume and number of molecules.

4. **Reviewing Other Laws**:
- **Charles' Law** relates to the volume and temperature of a gas at constant pressure.
- **Boyle's Law** relates to the volume and pressure of a gas at constant temperature.
- **Graham's Law** deals with the rates of diffusion of gases and does not pertain to volume and number of molecules directly.

**Hint**: Eliminate the laws that do not address the relationship between volume and the number of molecules.

5. **Conclusion**:
Since Avogadro's Law is the only law that states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules, the correct answer is:

**Answer**: Avogadro's Law

### Final Answer:
Equal volumes of all gases under the same temperature and pressure contain equal number of molecules according to **Avogadro's Law**.

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