Question

Why does the third shell of any element consists of 8 electrons although the capacity of the third shell is 18 ?
For example, potassium has electronic configuration of 2, 8, 8, 1. Should'nt it be 2, 8, 9 as third shell can occupy 18?

Answer 1

Due to the law of octate which is also used to distribute the elements in the modern periodic table of elements