Question

Taking the example of an element of atomic number 16 how the electronic configuration of the atom of an element relates to its position in the modern periodic table and how valency of an element is calculated on the basis of its atomic number

Answer 1

Electronic configuration of 16 = 1s² 2s² 2p6 3s2 3p4. The last electron is filled in 3p that is principal quantum number is 3 and it belongs to 3rd period and belong to p block and 12+4( electron in valence p)= 16 group.  This element is sulphur.