Question

Find the ratio of the following: $\left( Max\text{ }\left( M \right)\text{ }+Max\text{ }\left( N \right) \right)\text{ }/\text{ }\left( Max\text{ }\left( K \right)\text{ }+Max\text{ }\left( L \right) \right)$ where Max denotes the maximum number of electrons. K, L, M, N represents the shells.
(A) $4.$
(B) $5.$
(C) $6.$
(D) $7.$

Answer 1

We know that the shells are represented by the principal quantum numbers. The electrons present in a shell are double the square of principal quantum numbers. The Principal quantum number of the M shell is three. M shell has s, p, and d-orbitals.

Complete answer:
The electronic configuration can be written in KLMN format. Where the K, L, M, N shells represent the energy shells. The number of electrons accommodated in the shell is represented by the principal quantum number n, where the total number of an electron in the shell is given by the formula , $2{{n}^{2}}$ where n is the shell number.
In the structure of the atom, the center is known as the nucleus. The nucleus is surrounded by the orbits having electrons known as electron shells. The shell closest to the nucleus is known as the K shell. The next shell is known as the L shell. The next higher shell is M and then next is known as the N shell. The shell corresponds to the principal quantum numbers.
The s-orbital can have a maximum of two electrons and p-orbitals can have a maximum of six electrons, so the L shell can have a total of eight electrons. M shell has one s-orbital and one p-orbitals and d-orbitals. The s-orbital can have a maximum of two electrons, p-orbitals can have a maximum of six electrons and d-orbitals can have a maximum of ten electrons, so the M shell can have a total of eighteen electrons. We know that the M,N,L,K shell has a maximum $18,32,8,2$ electrons respectively.
$Max\left( M \right)=18,Max\left( N \right)=32,Max\left( L \right)=8,Max\left( K \right)=2,$ Substituting the values of all these into the ratio we get, $\dfrac{\left( 32+18 \right)}{\left( 2+8 \right)}=5.$
Therefore, the correct answer is option B.

Note:
Remember that a K shell has a maximum of two electrons. L shell has a maximum of eight electrons. N shell has a maximum of thirty-two electrons. A shell has one s-orbital, so it can have a total of two electrons maximum. L shell has one s-orbital and one p-orbital.