Question

How many unpaired electrons are present in cobalt $[Co]$ metal?

• A. 2
• B. 3
• C. 4
• D. 7

Answer 1

Answer: (B)

Co (atomic number $=27$)
$=1^2,2s^{2}2p^6,3s^{2}3p^{6}3d^7,4s^2$
Thus, number of unpaired electrons $=3$