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
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.