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Which of the following sets of quantum numbers represents the highest energy of an atom?
- n = 3, l = 0, m = 0, s = +1/2
- n = 3, l = 1, m = 1, s = +1/2
- n = 3, l = 2, m = 1, s = +1/2
- n = 4, l = 0, m = 0, s = +1/2
Correct answer: n = 3, l = 2, m = 1, s = +1/2
Solution
By the (n+l) rule: 3s (n+l=3), 3p (4), 3d (5), 4s (4). The 3d set has the highest n+l = 5, so n=3, l=2 represents the highest-energy orbital.
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