Question

Maximum value $(n+l+m)$ for unpaired electrons in second excited state of chlorine ${}_{17}Cl$ is:

• A. $28$
• B. $4$
• C. $20$
• D. None of these

Answer 1

The correct option is B $4$

The maximum value of (n+l+m) for all the unpaired electrons of chlorine in its second excited state .

Electronic configuration of chlorine atom

$1s^{2}2s^{2}2p^{6}3s^{2}3p^5$

First exited state chlorine atom

$1s^{2}2s^{2}2p^{6}3s^{1}3p^6$

Second exited state chlorine atom

$1s^{2}2s^{2}2p^{6}3s^{0}3p^{6}4s^1$

For only one unpaired electron present present in 4s orbital

Value of n =4

Value of l =0

Value of m =0

Therefore , the maximum value of (n+l+m) for all the unpaired electrons if chlorine in its second excited state .

=4+0+0

=4