Which set of quantum numbers is not allowed?
Correct answer: D. n=2,l=2,m1=1,ms=-1/2
- A. n=2,l=1,m1=0,ms=+1/2
- B. n=2,l=1,m1=-1,ms=+1/2
- C. n=2,l=0,m1=0,ms=-1/2
- D. n=2,l=2,m1=1,ms=-1/2
Explanation
For n = 2, the azimuthal quantum number l can only be 0 or 1, so l = 2 is not allowed; option d is therefore invalid. The likely mistake is choosing c because m1 is written as zero, but m1 = 0 is valid for an s orbital when l = 0.
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About Quantum Numbers
Quantum numbers describe an electron's energy level, subshell, orbital orientation and spin. You examine the principal, azimuthal, magnetic and spin quantum numbers, their allowed values, orbital capacity and how they determine electronic configurations and distinguish electrons within an atom.
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