MCQ
Which of the following is paramagnetic
- ✓${O_2}$
- B$C{N^ - }$
- C$CO$
- D$N{O^ + }$
✓
Answer
Correct option: A.
${O_2}$
(a) Electronic configuration of ${O_2}$ is
${O_2} = \sigma {(1s)^2}{\sigma ^ * }{(1s)^2}\sigma {(2s)^2}{\sigma ^ * }{(2s)^2}\sigma {(2{p_x})^2}\pi {(2{p_y})^2}$
$\pi {(2{p_z})^2}{\pi ^ * }{(2{p_y})^1}{\pi ^ * }{(2{p_z})^1}$
The molecule has two unpaired electrons So, it is paramagnetic
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