A : The gravitational force between the gas molecules is ineffective due to extremely small size and very high speed.
R : No force of interaction acts between molecules of an ideal gas.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then Mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To analyze the statements provided in the question, we will break down the assertion (A) and the reason (R) step by step.

### Step 1: Understand the Assertion (A)
The assertion states that "The gravitational force between the gas molecules is ineffective due to extremely small size and very high speed."

- **Explanation**: Gravitational force is generally very weak compared to other forces, especially at the molecular level. Gas molecules are extremely small and move at very high speeds, which means that the effect of gravity on them is negligible.

### Step 2: Understand the Reason (R)
The reason states that "No force of interaction acts between molecules of an ideal gas."

- **Explanation**: This statement is based on the assumptions of an ideal gas. In the kinetic theory of gases, it is assumed that gas molecules do not exert any forces on each other except during elastic collisions. Therefore, there are no significant interactions between the molecules.

### Step 3: Evaluate the Relationship Between A and R
Now, we need to determine if the reason (R) provides a valid explanation for the assertion (A).

- **Analysis**: While both statements are true, the reason does not explain why the gravitational force is ineffective. The assertion explains that gravitational force is negligible due to the small size and high speed of the molecules, while the reason simply states that there are no interaction forces in an ideal gas. The reason does not address the gravitational force directly.

### Conclusion
Based on the analysis, we can conclude that:
- The assertion (A) is correct.
- The reason (R) is also correct, but it does not provide a valid explanation for the assertion.

Thus, the correct answer is that the assertion is true, and the reason is true but does not explain the assertion.

### Final Answer
- Assertion (A) is true.
- Reason (R) is true but does not explain (A).

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