Q. Transition elements exhibits variable valencies because they release electrons from the following orbits
A) $ns$
B) $ns$ and $np$
C) $(n - 1)d$ and $ns$
D) $(n - 1)d$
Explanation
(c)
Variable valency is due to the participation of electron from $(n - 1)d$ and $ns$ levels in bond formation
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.