The atoms of covalent materials are firmly bonded to each other in stable molecules, but these molecules are not generally very strongly attracted to other molecules of the material. This generally leads to low melting points in the covalent solids and high melting points in the ionic solids. For example, the carbon tetrachloride molecule CCl4, is a non-polar covalent molecule. Its melting point is -23 ° C. In contrast, the NaCl ionic solid has a melting point of 800 ° C.
