Question

An element ‘X’ belongs to 3rd period and group 16 of the Modern Periodic Table.

a) Determine the number of valence electrons and the valency of ‘X’.

b) Molecular formula of the compound when ‘X’ reacts with hydrogen and write its electron dot structure.

c) Name the element ‘X’ and state whether its a metal or a non- metal.

Answer 1

1) Since the element belongs to group 16, therefore its electronic configuration is 2, 8, 6, and hence it has 6 valence electrons. Its valency is 8 – 6 = 2 (-2).

2) Molecular formula is XH2
..
Electron dot structure. ..X..

3) Element X is Sulphur. It is non metallic