Electronic configuration of first 20 elements

Explanation:

Electronic Configuration of First 30 Elements with Atomic Numbers

Atomic NumberName of the ElementElectronic Configuration

18Argon (Ar)[Ne] 3s2 3p6

19Potassium (K)[Ar] 4s1

20Calcium (Ca)[Ar] 4s2

21Scandium (Sc)[Ar] 3d1 4s2

26 more rows

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.