What are the number of sub-levels and electrons for the first four principal quantum numbers?

1 Answer
Oct 23, 2015

For quantum number 1, the number of sub level is 1, number of electrons= 2.
For quantum number 2, no. of sub levels are 2, no. of electrons= 8. For quantum no. 3, sub levels are 3 and no. of electrons are 18.
For 4th quantum no. sub levels are 4 and electrons are 32.

Explanation:

You can easily calculate it with this method :

  1. Suppose the principal quantum number is symbolized as n the Azimuthal or secondary quantum number is symbolized as l
    the magnetic Q.N is m
    and the spin Q.N is s.

  2. n = which energy shell it is; l = number of sub-shells; m = number of orbitals as well as electrons.
    l =0, n-1 and m = +- l = -l, 0, +l.

  3. For example, in case of principal quantum number 2,
    the result of l is = n-1 = 2-1 = 1, which means the number of subshells are two : 0 and 1.

Now the result for m is : 0 = s (one orbital of subshell s) = 2 electrons. And for 1 = -1, 0, +1 = P_x, P_y and P_z (3 orbitals of subshell p), electron = 6 ( each orbital can contain maximum 2 electrons ) .

So the total number of electrons for principal quantum number 2 is 8 .