Q. The oxidation state and effective atomic number(EAN) of cobalt $\left( {CoF}_{6} \right)^{2 -}\$are respectively
A) 3 and 36
B) 4 and 35
C) 4 and 37
D) 2 and 35
Explanation
(b)
Effective atomic number (EAN) =Atomic no. of metal
-Oxidation no.+ Coordination no.$\times$2
For$\left\lbrack {CoF}_{6} \right\rbrack^{2 -}\$, the oxidation state of cobalt is 4.
EAN=(27-4)+6$\times$2
=23+12=35
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.