How many electrons in an atom may have the following quantum numbers? n = 4, ms= -12 - Chemistry

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Numerical

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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Chapter 2: Structure of Atom - EXERCISES [Page 71]

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NCERT Chemistry Part 1 and 2 Class 11
Chapter 2 Structure of Atom
EXERCISES | Q 2.31 - (a) | Page 71

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