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.
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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.
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