Q. Which one of the following pairs of elements is called ‘chemical twins’ because of their very similar chemical properties?
A) Mn and W
B) Mo and Tc
C) Fe and Re
D) Hf and Zr
Explanation
(d)
$Zr$ and $Hf\$possess similar atomic size and hence are called twins of Periodic Table. It is due to lanthanide contraction.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.