Question

An element belongs to group II. What would be its valency? Write the formula of molcules of compounds it will form with elements in VA, VIA and VIIA groups.

Answer 1

VIA

Symbols		Valencies
Magnesium	Oxide	Magnesium	Oxide
Mg	O	2+	2-

(1)  Write the symbol

On the left-hand side Calcium	On the right-hand side Chloride
Ca	Cl

(2) Write the valency of the symbols 

At the top right corner Positive ion	At the top right corner  Negative ion
Ca2+	Cl1-

(3) Interchange the valency 

number (Ignore the (+)and (-) signs)

(4) Write the interchanged numbers at the base 

but ignore the + and the - sings 

`"Ca"_1`                     `"Cl"_2`