Assertion: All molecules of an ideal gas more with the same speed.
Reason: There is no attraction between the molecules in an ideal gas.

Options

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

Answer

To solve the question regarding the assertion and reason about the behavior of molecules in an ideal gas, we will analyze both statements step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "All molecules of an ideal gas move with the same speed."
- In reality, this is not true. In an ideal gas, molecules have a distribution of speeds described by the Maxwell-Boltzmann distribution. Therefore, molecules do not all move with the same speed.

2. **Understanding the Reason**:
- The reason states that "There is no attraction between the molecules in an ideal gas."
- This statement is true. An ideal gas is defined as a gas where the molecules do not exert any forces on each other except during elastic collisions. This means there is no attractive or repulsive force acting between the molecules.

3. **Evaluating the Assertion and Reason**:
- Since the assertion is false (not all molecules move with the same speed), and the reason is true (there is no attraction between molecules), we can conclude that the assertion does not logically follow from the reason.

4. **Final Conclusion**:
- The assertion is false, while the reason is true. Therefore, the correct relationship between the two is that the reason does not support the assertion.

### Summary:
- Assertion: False (not all molecules have the same speed).
- Reason: True (no attraction between molecules in an ideal gas).
- Conclusion: The assertion is false, and the reason is true.