Zeev's Turnips Talk Politics (ZTTP)

[Zeev Hed]

Water starts to expand as it cools from 4 C, while still a liquid, rather than continue and contract as it does from 100 C to 4 C. Furthermore, almost all solid phases (I know of two other substances that violate that law, Si and Fe) are denser than their counterpart liquid phase. There are few substances that do not have a liquid phase under normal conditions (Carbon, the oxides of Mo and W and CO2 for instance, though the later can be made fluid, or even a critical fluid, at pressures above about 100 atmospheres).

Zeev