WAEC Chemistry 2020 Paper

Concept:A giant covalent structure is a large network of atoms joined by strong covalent bonds.Explanation:In a giant covalent oxide, many atoms are linked in a regular three-dimensional pattern.Silicon dioxide, $\mathrm{SiO}_{2}$, is a common example: each silicon atom bonds covalently to four oxygen atoms, and each oxygen atom bonds to two silicon atoms.This forms a strong, rigid, extended structure.The given options are hydroxides, not oxides, and they do not have giant covalent structures.Answer:None of the given options is an oxide with a giant covalent structure.An oxide that has this structure is silicon dioxide, $\mathrm{SiO}_{2}$.