Which combination of quantum numbers is not allowed?

Updated: Nov 20, 2022

Which of the following combinations of quantum numbers do not represent permissible solutions of the Schrodinger equation for the electron in the hydrogen atom? (In other words, which combination of quantum numbers is not allowed?) (Combinations are listed as follows: n, l, m(l), m(s).)

A) 9 8 –4 1/2

B) 8 2 2 1/2

C)6 –5 –1 1/2

D) 6 5 –5 1/2

E) All are allowed

In order for us to do this problem, we have to get some rules down about the four quantum numbers.

The first quantum number is n, principle energy level, and n can be any integer 1 2 3 and so on.

The next quantum number is l and l has a rule that depends on n. l has to go from 0 to n minus 1. For example if n=3, l =0,1,2.

Next quantum number ml depends on l it can go from minus l to zero to plus l .For example, for l=2, ml = -2,-1,0,1,2.

ms = 1/2 or -1/2

Therefore, choice C is wrong because if n=6, the possible values for l are 0,2,3,4,5. Not -5 like the answer choice has which is impossible.

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