Question

Zr and Hf exhibit similar properties

Answer 1

Zr and Hf exhibit similar properties due to lanthanoid
contraction.
F and D orbitals are very large, and hence electrons are scattered.
Electrons present in f subshell doesnot do good
shielding . So,when atomic number or effective nuclear charge increases, size gets constricted.
So, Halfenium and Zirconium has almost identical atomic sizes, and hence similar properties.