QAIPM-2000-Ch-2956: NEET 2000 Chemistry - Class 11 AIPM-2000-Ch-2956 Solution: Which species does not exhibit paramagnetism?

Those species which have unpaired electrons are called paramagnetic species. And those species which have no unpaired electrons are called diamagnetic species. (A) N 2 + has 13 electrons. Moleculer orbital configuration of N 2 + = _ 1 s 2 _ 1 s 2 _ _ 2 s 2 _ 2 s 2 _ � 2 p x 2 = � 2 p y 2 _ 2 p z 1 Here 1 unpaired electrons present, so it is paramagnetic. (B) Molecular orbital configuration of O 2 _ (17 electrons) is _ 1 s 2 _ 1 s 2 _ _ 2 s 2 _ 2 s 2 _ _ 2 p z 2 � 2 p x 2 = � 2 p y 2 � 2 p x 2 _ = � 2 p y 1 _ Here 1 unpaired electrons present, so it is paramagnetic. (A) CO has 14 electrons. Moleculer orbital configuration of CO = _ 1 s 2 _ 1 s 2 _ _ 2 s 2 _ 2 s 2 _ � 2 p x 2 = � 2 p y 2 _ 2 p z 2 Here 0 unpaired electrons present, so it is diamagnetic. (D) Molecular orbital configuration of NO (15 electrons) is _ 1 s 2 _ 1 s 2 _ _ 2 s 2 _ 2 s 2 _ _ 2 p z 2 � 2 p x 2 = � 2 p y 2 � 2 p x 1 _ = � 2 p y o _ Here 1 unpaired electrons present, so it is paramagnetic.