In the following question, a statement of assertionn is followed by a statement of reason. Mark the correct choice.
Assertion: Greater the value of van der waals constant 'a' easier is the liquifaction of a gas.
Reason: 'a' indirectly measures the magnitude of attractive forces between the molecules.

Options

A. both assertion and reason are true and reason is the correct explanationn of assertion
B. both assertionn and reason are true but reason is not the correct explanation of assertion
C. Assertionis true but reason is false.
D. both assertion and reason are false.

Answer

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

### Step 1: Understand the Assertion
The assertion states: "Greater the value of van der Waals constant 'a', easier is the liquefaction of a gas."

- The van der Waals constant 'a' is a measure of the attractive forces between gas molecules.
- A higher value of 'a' indicates stronger intermolecular attractions.

### Step 2: Understand the Reason
The reason states: "'a' indirectly measures the magnitude of attractive forces between the molecules."

- This statement is true because the constant 'a' in the van der Waals equation accounts for the attractive forces that cause gas molecules to come together and form a liquid.

### Step 3: Analyze the Relationship
Now, we need to see how both statements relate to each other.

- If 'a' is greater, it means there are stronger attractive forces, which indeed makes it easier for the gas to liquefy.
- Therefore, the assertion is true because a higher value of 'a' correlates with easier liquefaction due to stronger intermolecular forces.

### Step 4: Conclusion
Both the assertion and the reason are true, and the reason correctly explains the assertion.

Thus, the correct choice is that both the assertion and reason are true, and the reason explains the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason explains the assertion.

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