Binary compounds of zinc are known for most of the metalloids and all the nonmetals except the noble gases. The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric, dissolving in both strong basic and acidic solutions. The other chalcogenides (ZnS, ZnSe, and ZnTe) have varied applications in electronics and optics. Pnictogenides (Zn 3N 2, Zn 3P 2, Zn 3As 2 and Zn 3Sb 2), the peroxide (ZnO 2), the hydride (ZnH 2), and the carbide (ZnC 2) are also known. Of the four halides, ZnF 2 has the most ionic character, while the others (ZnCl 2, ZnBr 2, and ZnI 2) have relatively low melting points and are considered to have more covalent character.
