The difference between light zinc oxide and heavy zinc oxide lies in the different methods of producing zinc oxide. Zinc oxide produced by direct method is heavy zinc oxide; Zinc oxide produced by indirect method is light zinc oxide.

Examples of direct method: obtained by calcining zinc carbonate. ZnCO3=ZnO+CO2↑

The indirect method is the zinc obtained by electrolysis reacts with oxygen at high temperature to form zinc oxide. The reaction equation is:2Zn+O2=2ZnO

From the reaction conditions and methods, the purity of zinc oxide produced by indirect method is higher than that by direct method. That is, the quality of light zinc oxide is better than that of heavy zinc oxide.