Question

The electronic configuration of sulphur is:
(A)- ${\text{K}}\left( {\text{2}} \right){\text{,L}}\left( {\text{8}} \right){\text{,M}}\left( {\text{6}} \right)$
(B)- ${\text{K}}\left( {\text{2}} \right){\text{,L}}\left( {\text{8}} \right){\text{,M}}\left( 8 \right)$
(C)- ${\text{K}}\left( {\text{2}} \right){\text{,L}}\left( 6 \right)$
(D)- ${\text{K}}\left( {\text{2}} \right){\text{,L}}\left( {\text{8}} \right)$

Answer 1

Hint: For showing the electronic configuration of any atom, first of all we should know about the total number of electrons present in that atom. And the number of electrons in an atom is always equal to the Atomic Number of that atom.

Complete answer:
In the periodic table Sulphur is denoted as ${}_{{\text{16}}}^{{\text{32}}}{\text{S}}$, where upper quantity displays the atomic mass (${\text{A}}$) of the sulphur and lower quantity displays the atomic number (${\text{Z}}$).
-As we know that the number of protons present inside the nucleus or no. of electrons present outside the nucleus in the orbital is equal to the atomic number of that atom.
i.e. Atomic Number (${\text{Z}}$) = No. of electrons = No. of protons
-From ${}_{{\text{16}}}^{{\text{32}}}{\text{S}}$ it is clear that, atomic number of sulphur is 16 and total number of electrons present in sulphur is also 16.
-Electronic configuration of sulphur is shown as follow:
${\text{1}}{{\text{s}}^{\text{2}}}{\text{,2}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{p}}^{\text{6}}}{\text{,3}}{{\text{s}}^{\text{2}}}{\text{3}}{{\text{p}}^{\text{4}}}$
-From above configuration it is clear that total two electrons are present in innermost or 1st shell, eight electrons are present in the 2nd shell ($2 + 6$) and six electrons ($2 + 4$) are present in the 3rd shell after nucleus of the sulphur atom.
-As we know that the 1st shell after the nucleus is known by the symbol ‘K’, second shell after nucleus is known by the symbol ‘L’, third shell after nucleus is known by the symbol ‘M’ and so on.

Note:
Here some of you may think that shell K is the outermost shell when we start counting from outside, but that will be wrong because innermost shell is named as K.