Which of the following electron distributions among the molecular orbitals best describes the NO molecule?
A) IV
B) V
C) III
D) I
E) II

Question

Which of the following electron distributions among the molecular orbitals best describes the NO molecule? 
A) IV 
B) V 
C) III 
D) I 
E) II

Quizplus · Accepted Answer

The NO molecule has a total of 10 valence electrons (5 from nitrogen and 5 from oxygen). The molecular orbital diagram for NO should have 10 electrons placed in the 5 molecular orbitals: sigma(2s), sigma*(2s), pi(2p)x, pi(2p)y, and sigma(2p)z. Among the given options, only option B has the correct electron distribution, with 5 bonding electrons and 5 antibonding electrons. Option B also correctly shows that the highest occupied molecular orbital (HOMO) is the pi(2p)x orbital.

Which of the Following Electron Distributions Among the Molecular Orbitals