Network solid or covalent solid is a compound in which the atoms are bonded together by covalent bonds in a continuous network. Out of given solids, network solids are; AlN, diamond and SiO2. Ionic solid are composed of ions (cations and anions) held together by electrostatic forces. Out of given solids, ionic solids are; NaCl,MgO,CaF2, ZnS.