Question

The lanthanide contraction is responsible for the fact that:

• A. Zr and Zn have the same oxidation state
• B. Zr and Hf have about the same radius
• C. Zr and Nb have similar oxidation state
• D. Zr and Y have about the same radius

Answer 1

Answer: (B)

Zr and Hf have about the same radius

Answer 2

Lanthanide contraction, cancels almost exacdy the normal size increase on descending a group of transition elements, thus Nb and Ta and, Zr and Hf have same covalent and ionic radii.