Chemical Bonding And Molecular Structure Question 368
Question: In $ O_2^{-}, $
$ O_2 $ and $ O_2^{-2} $ molecular species, the total number of antibonding electrons respectively are [DCE 2003]
Options:
A) 7, 6, 8
B) 1, 0, 2
C) 6, 6, 6
D) 8, 6, 8
Show Answer
Answer:
Correct Answer: A
Solution:
Molecular orbital electronic configuration of these species are : $ O_2^{-}(17{e^{-}})= $
$ \sigma 1s^{2}{{\sigma }^{*}}1s^{2},\sigma 2s^{2}{{\sigma }^{*}}2s^{2},\sigma 2p_x^{2},\pi 2p_y^{2}, $
$ \pi 2p_z^{2},{{\pi }^{*}}2p_y^{2}{{\pi }^{*}}2p_z^{1} $
$ O_2(16e)= $
$ \sigma 1s^{2}{{\sigma }^{*}}1s^{2},\sigma 2s^{2}{{\sigma }^{*}}2s^{2},\sigma 2p_x^{2},\pi 2p_y^{2}, $
$ \pi 2p_z^{2}{{\pi }^{*}}2p_y^{1}{{\pi }^{*}}2p_z^{1} $
$ O_2^{2-}(18e)= $
$ \sigma 1s^{2}{{\sigma }^{*}}1s^{2},\sigma 2s^{2}{{\sigma }^{*}}2s^{2},\sigma 2p_x^{2},\pi 2p_y^{2}, $
$ \pi 2p_z^{2}{{\pi }^{*}}2p_y^{2}{{\pi }^{*}}2p_z^{2} $
Hence number of antibonding electrons are 7,6,and 8 respectively.