Question

Given below two statements: One is labelled as Assertion (A) and other is labelled as Reason (R).
Assertion (A) : Non-polar materials do not have any permanent dipole moment.
Reason (R) :When a non-polar material is placed in an electric field, the centre of the positive charge distribution of it’s individual atom or molecule coincides with the centre of the negative charge distribution.
In the light of above statements, choose the most appropriate answer from the options given below.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct and (R) is not the correct explanation of (A).
• C. (A) is correct but (R) is not correct.
• D. (A) is not correct but (R) is correct.

Answer 1

The Correct Option is C

To solve the given question, we need to analyze both the Assertion (A) and Reason (R) statements provided and then determine the accurate relationship between them.

Assertion (A): Non-polar materials do not have any permanent dipole moment.

Explanation: Non-polar molecules have an equal distribution of charge, which means that the centers of positive and negative charges coincide, resulting in no permanent dipole moment. Thus, the assertion is indeed correct.

Reason (R): When a non-polar material is placed in an electric field, the center of the positive charge distribution of its individual atom or molecule coincides with the center of the negative charge distribution.

Explanation: While it's true that in non-polar materials, without an external field, the centers of positive and negative charges coincide, when placed in an electric field, this is not entirely true. In an external electric field, non-polar molecules can become slightly polarized due to the shifting of charges, creating temporary dipoles. Hence, the reason is not entirely correct in the context of providing a valid explanation for the assertion.

Hence, based on the above reasoning:

• The Assertion (A) is correct because non-polar materials inherently lack a permanent dipole moment.
• The Reason (R) is not correct since it does not accurately explain the situation under an external electric field in relation to non-polar molecules.

Thus, the correct answer is: (A) is correct but (R) is not correct.