Question

An element X is in group 2 of the periodic table what will be the formula of its oxide?

Answer 1

We know that oxygen has 6 valence electrons and needs 2 more electrons to complete its octet. Therefore, the valency of oxygen O is 2, that is, (8 - 6). Both X and O have the same valency. When one atom of X combines with one atom of O, an ionic compound of the formula XO is formed.