alleryStart learning →Electronic configuration of sodium (Z = 11) is:
A2, 8, 2
B2, 8, 1
C2, 9
D2, 7, 2
Answer & Solution
Correct answer: B. 2, 8, 1
1. Sodium has 11 electrons in a neutral atom.
2. K shell holds 2; L shell holds 8; M shell holds the remainder.
3. So arrangement is 2, 8, 1.
4. Sodium has one valence electron, placing it in Group 1.
_Source: Selina Concise Chemistry ICSE Class 9, Ch 4 'Atomic Structure'_
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