An element X shows 2 valencies of 3 and 5. Work out the formula of 2 oxides of this element.

Let the element be “X”

Case 1:

Valency of X= +3

Valency of Oxide “O”= -2

Therefore, the formula for the oxides of the element X= X₂O₃

Case 2:

Valency of X= +5

Valency of O= -2

Therefore, the formula for the oxides of the element X= X₂O₅