Question

Assertion (A) Separation of $Zr$ and $Hf$ is difficult.
Reason (R) Because $Zr$ and $Hf$ lie in the same group of the periodic table.

• A. Both $A$ and $R$ are correct; $R$ is the correct explanation of $A$.
• B. Both $A$ and $R$ are correct; $R$ is not the correct explanation of $A$.
• C. $A$ is correct; $R$ is incorrect.
• D. $R$ is correct; $A$ is incorrect.

Answer 1

Answer: (B)

Assertion and Reason are true but Reason is not correct explanation of Assertion. Separation of $Zr$ and $Hf$ is difficult This is due to lanthanoid contraction which causes almost similar radii of both of them.