Assertion: Equal moles of different substnaces contains same
number of constituent particles.
Reason: Equal weights of different substances contain the samme number of contituent particles.

Options

A. If both assertion and Reason are true and the Reason is the correct explanation of the assertion.
B. If both assertion and Reason are true but the reason is not the
correct explanation of the assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Equal moles of different substances contain the same number of constituent particles."
- According to Avogadro's law, equal volumes of gases at the same temperature and pressure contain an equal number of molecules. This implies that equal moles of any substance, whether it is a gas, liquid, or solid, will contain the same number of constituent particles (atoms, molecules, etc.).
- Therefore, the assertion is **True**.

2. **Understanding the Reason**:
- The reason states that "Equal weights of different substances contain the same number of constituent particles."
- This statement is not universally true. The number of particles in a given weight of a substance depends on its molar mass. Different substances have different molar masses, so equal weights do not guarantee an equal number of particles.
- For example, 10 grams of hydrogen (H2) will contain many more molecules than 10 grams of gold (Au) because gold has a much higher molar mass. Thus, the reason is **False**.

3. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer to the question is that the assertion is true but the reason is false.

### Final Answer:
- Assertion: True
- Reason: False