Question

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

• A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
• B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
• C. Assertion is true but Reason is false
• D. Both Assertion and Reason are false

Answer 1

Answer: (B)

Separation of $Zr$ and $Hf$ is difficult because both have very similar physical and chemical properties, also both have almost similar atomic radii $( Zr =160\, pm$ and $Hf =159\, pm )$ due to lanthanoide contraction.