Question

Covalency of chlorine atom in 2nd excited state will be

Answer 1

Electronic configuration of chlorine is:

1s^2 2s^2 2p^6 3s^2 3p^5

First excited state will be: 1s^2 2s^2 2p^6 3s^1 3p^6

Second excited state will be: 1s^2 2s^2 2p^6 3s^0 3p^6 4s^1

One unpaired electron present in 4s orbital

n =4

l =0

m =0

n+l+m =4+0+0 = 4

Therefore, the maximum unpaired electrons i.e. covalency of chlorine in second excited state will be 4

Answer 2

[Ne] 3s2 3p3 4s2

that is Max covalency =4