An element X belongs to 3rd period and group 16 of the Modern Periodic Table. Determine the number of valence electrons and the valency of X?

Number of valence electrons for the element in group 16 and period 3 is 6. The maximum capacity of M shell as valence shell is 8. Hence, valency of element X is 2 (8-6=2) and number of valency electrons is 6.