Question

A metal X is in the first group of the periodic table. What will be the formula of its oxide?

Answer 1

The elements in the first group of the periodic table have a valency of 1. As the metal X is in the first group, its valency is 1. We know that the valency of oxygen is 2 because it needs two electrons to complete its outer shell of 8. From this, we can conclude that two atoms of metal X will combine with one atom of oxygen to form an oxide X₂O. Therefore, the formula of the oxide of metal X is X₂O.