Question

The period with electrons in the shells k.l.m

Answer 1

Here is Ur answer,

Period 3 contains elements whose k,l,m shells are filled with electrons.

Hope it helps u......

Answer 2

Explanation:

Third period is the period which contains electrons in K, L, M shells. Distribution of electrons in these shells will be as 2 electrons in K shell, 8 electrons in L shell and 18 electrons in M shell.

M shell can accommodate up to 18 electrons.

For example, atomic number of aluminium is 13 and it belongs to third period.

It's electronic configuration is as follows.

                  $1s^{2}2s^{2}2p^{6}3s^{2}3p^{1}$

That is, there are 2, 8, 3 electrons in K, L, M shell respectively.