Chemistry-Transition Elements

NEET Chemistry Transition Elements Assertion Reason Question

Type: Assertion Reason-assertion-Hard-Class 12

Assertion (A): The lanthanoid contraction results in the second and third d series having similar radii and properties. | Reason (R): The imperfect shielding of 4f electrons by each other causes a decrease in size across the series.

A

Both A and R are true and R is the correct explanation of A.

B

Both A and R are true but R is not the correct explanation of A.

C

A is true but R is false.

D

A is false.

Correct Answer

Option A

Detailed Explanation

The lanthanoid contraction leads to similar radii in the second and third d series due to the imperfect shielding of 4f electrons, as stated in Chunk 1.

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