Q. Which among the following elements have lowest value of $\ IE_{1}$?
A) Pb
B) Sn
C) Si
D) C
Explanation
(b)
The ionisation energy of Tin (Sn) is less than that of lead (Pb). It is due to the poor sheilding of $d$- and $f$-electron in Pb, due to which it feels greater attraction from nucleus.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.