Key Idea For an electron, n may be 0,1,2… and l=0 to n−1 and m=−l to +l (including 0) and s=±21 Hence, if nl m s=3=0 to (3−1)=0,1,2=−l to +1=−2−1,0,+1,+2=±21 Therefore, option (c) is not a permissible set of quantum numbers.
NEET UG 2009 — Chemistry Physical Chemistry
Which of the following is not permissible arrangement of electrons in an atom ?
Held on 30 Apr 2009 · Verified 9 Jul 2026.
n=4,l=0, m=0, s=−1/2
n=5,l=3, m=0, s=+1/2
n=3,l=2, m=−3, s=−1/2
n=3,l=2, m=−2, s=−1/2
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