

Hi there,
Please take a look at the answer below:
Rules:
1. If n gives the number of orbit or energy level, then 2n2 gives the maximum number of electrons possible in a given orbit or energy level.
K shell - maximum of 2 electrons
L shell - maximum of 8 electrons
M-shell - maximum of 18 electrons
2. The outermost orbit should not have more than 8 electrons.
3. Electrons to be filled stepwise in different orbits.
Thanks and Regards
