How many electron in an atom could have these sets of quantum numbers? n=5 l=3?

14

Explanation:

There are 4 quantum numbers:

n: principal quantum number - describes the electron shell(varies from 1 to 7);

l: azimuthal quantum number - describes the subshell (varies from 0 to 3);

m: magnetic quantum number - describes the specific orbital (varies from -l to +l passing by 0);

s: spin quantum number - describes the spin of the electron (-1/2 or +1/2).

In each orbital (described by m) the maximum number of electrons is 2, so, for subshell 3, the magnetic numbers are  -3,-2,-1,0,+1,+2, and +3. So there are 7 orbitals. The maximum number of electrons that can have n=5 and l= 3 is 14.