Question

what is meant by monomeric and dimeric nature of oxides?

Answer 1

Monomeric and dimeric nature of oxides means that monomeric oxide has one oxygen atom in its structure (monooxide), while dimeric oxide corresponds to the structure with two oxygen atoms (dioxide).
For example, Potassium oxide (K2O), has only one atom of oxygen, and is thus a monoxide. Water (H2O) is a monoxide; another well known monoxide is carbon monoxide (CO).
Other examples of dioxides: nitrogen dioxide (NO2); carbon dioxide, CO2; chlorine dioxide (ClO2); sulfur dioxide (SO2).