Question

What is the valency of oxide?

Answer 1

Oxide:

• A chemical compound with at least one oxygen atom and one additional element in its chemical formula is known as an oxide.
• Oxide is a dianion of oxygen, an $\left({\mathrm{O}}^{2-}\right)$ion. As a result, metal oxides usually contain oxygen as an anion in the oxidation state of 2.

Examples:

• Magnesium oxide $\left(\mathrm{MgO}\right)$, Aluminium oxide $\left({\mathrm{Al}}_2{\mathrm{O}}_3\right)$, Iron oxide $\left({\mathrm{Fe}}_2{\mathrm{O}}_3\right)$, Copper oxide $\left(\mathrm{CuO}\right)$, etc.

Valency of oxide:

• The atomic number of oxygen is 6. Therefore, it has 6 electrons. It needs two more electrons from the other atoms to complete its octet configuration (outermost shell with 8 electrons).
• Hence, the valency of the oxide 2.