Question

Explain the arrangement and distribution of electrons in the various shells with reference to an atom in general and to an atom of potassium ‘³⁹₁₉K’ with special reference to the 2n² rule.

Answer 1

Arrangement of electrons: Direction of electrons in various shells is given by a formula 2n² where is the number
n = 1 In first shell there can be maximum of 2 × (1)² = 2 electrons.
n= 2 In second shell there can be maximum of 2 (2)² = 8 electrons.
n = 3 In third shell there can he maximum of 2 (3)² = 2 × 9 = 18 electrons and soon.
But there cannot be more than 8 electrons in the outermost shell and cannot be more than 18 electrons in penultimate orbit
Higher shell will start only when the lower shells are completely filled.
³⁹₁₉K has 19 electrons
In the first shell or K shell will have 2 electrons.
2nd shell or L shell 8 electrons.
3rd shell or M shell 8 electrons
and 4th or N shell 1 electron.