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Question
How many electrons in an atom may have the following quantum numbers?
n = 4, `m_s = -1/2`
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Solution
Total number of electrons in an atom for a value of n = 2n2
∴ For n = 4,
Total number of electrons = 2 (4)2
= 32
The given element has a fully filled orbital as
1s2 2s2 2p6 3s2 3p6 4s2 3d10.
Hence, all the electrons are paired.
∴ Number of electrons (having n = 4 and `m_s = -1/2`) = 16
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