E. Entropy is lower in covalently bonded solids than in solids with partial metallic character (left).

The entropy is lower in framework solids such as diamond and gray tin, because the covalent bonds hold the atoms in a more orderly arrangement than do the nondirectional attractions of metals. For the very same reasons, covalent three-dimensional network solids are harder and more resistant to deformation.

F. Entropy is lower in extended sheet structures than in molecular solids).

Again, the covalently bonded infinite sheets are more ordered than are P₄ molecules, which are held together in the solid only by weak van der Waals forces.