According to molecular orbital theory, which one of the following will indicate two unpaired electrons?
Correct answer: B. O2
- A. N2
- B. O2
- C. F2
- D. He22+
Explanation
The correct answer is O2. According to molecular orbital theory, O2 has a configuration with two unpaired electrons in the π* 2p molecular orbitals, making it paramagnetic. In contrast, N2 and F2 have all paired electrons, making them diamagnetic. He22+ is a hypothetical species and unlikely to have unpaired electrons.
Last updated
About Electronic Configuration
Electronic configuration describes how electrons occupy shells, subshells and orbitals around an atom. Questions use the Aufbau principle, Pauli exclusion principle and Hund's rule to write configurations, identify valence electrons, form ions and explain periodic trends, including common exceptions such as chromium and copper.
Practise Atomic Structure
922 free Atomic Structure MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A neutral atom A has the electronic configuration: 1s2 2s2 2p6 3s2 3p6 4s1. It will gain or lose electron/s to form most probably an ion of valence:
According to Hund's rule, electrons entering a set of degenerate orbitals will
According to the n plus l rule, which orbital is filled first?
After 3s the sub-shell begin to fill is
Alkali and alkaline earth metals impart colours when heated over burner. It is due to______________?