Question

The maximum number of electrons in the first shell is ___.

Answer 1

The number of electrons in any shell is calculated using the formula $2n^2$ where n is the number of the shell.

1. The first shell, also called the K shell is occupied by $2n^2=2\left(1^2\right)=2$ electrons.
2. The innermost shell is filled first which has only 1 subshell called the s subshell.
3. Subsequently, higher shells such as L shell is filled with $2n^2=2\left(2^2\right)=8$ electrons in the same manner

Hence, The maximum number of electrons in the first shell of the atom is 2.