Why `Zr` and `Hf` or `Nb` and `Ta` exhibit similar properties?   Or Zirconium (atomic number40)
Channel: Doubtnut
Date: 2020-04-12

Why `Zr` and `Hf` or `Nb` and `Ta` exhibit similar properties?   Or Zirconium (atomic number40) and hafnium number 72) occur together  in minerals and they exhibit similar properties. Give reasons.