Question:
If \(n,l,m\) and \(s\) represent the symbols of quantum numbers, the impossible quantum number set for the electron in terms of \(n,l,m\) and \(s\) respectively is
If \(n,l,m\) and \(s\) represent the symbols of quantum numbers, the impossible quantum number set for the electron in terms of \(n,l,m\) and \(s\) respectively is
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For a given \(l\), magnetic quantum number \(m\) can take values from \(-l\) to \(+l\). If \(l=0\), then only \(m=0\) is possible.
Updated On: May 7, 2026
- \(2,0,-1,+\frac{1}{2}\)
- \(3,0,0,-\frac{1}{2}\)
- \(4,1,+1,+\frac{1}{2}\)
- \(3,2,-1,-\frac{1}{2}\)
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The Correct Option is A
Solution and Explanation
For quantum numbers, the rules are:
Principal quantum number:
\[
n=1,2,3,\ldots
\]
Azimuthal quantum number:
\[
l=0,1,2,\ldots,n-1.
\]
Magnetic quantum number:
\[
m=-l,\ldots,0,\ldots,+l.
\]
Spin quantum number:
\[
s=+\frac{1}{2}\quad \text{or}\quad -\frac{1}{2}.
\]
Now check option (A):
\[
n=2,\quad l=0,\quad m=-1,\quad s=+\frac{1}{2}.
\]
If:
\[
l=0,
\]
then magnetic quantum number can only be:
\[
m=0.
\]
But option (A) gives:
\[
m=-1.
\]
This is not allowed.
Therefore, option (A) is impossible.
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