question_answer

If the magnetic moment of a dioxygen species is 1.73 B.M, it may be   [JEE MAIN Held on 09-01-2020 Morning]

A) \[O_{2}^{-}\] or \[O_{2}^{+}\]          

B) \[{{O}_{2}},O_{2}^{-}\] or \[O_{2}^{+}\]

C) \[{{O}_{2}}\] or \[O_{2}^{+}\]           

D) \[{{O}_{2}}\] or \[O_{2}^{-}\]

Correct Answer: A

Solution :

[a] In case of \[{{O}_{2}}\]:

Species	No. of unpaired e-
\[{{O}_{2}}\]	2
\[O_{2}^{-}\]	1
\[O_{2}^{+}\]	1
\[O_{2}^{2-}\]	0

            Magnetic moment = \[\sqrt{n\left( n+2 \right)}\]BM = 1.73BM \[\Rightarrow \]n = no. of unpaired electrons = 1