Water. A liquid compound that consists of 11.188% of hydrogen and 88.812% of oxygen by weight and in the proportions of two hydrogen atoms (q.v.) to one oxygen atom (H2O). It is an odorless, tasteless, colorless and transparent liquid that freezes to a solid state at 32¦F (0¦C) and boils and is converted into a vapor (q.v.) state at 212¦F (100¦C). In its liquid state it serves as the standard for specific gravity (q.v.) and specific heat (q.v.) measurements. It is the most important solvent (q.v.) in nature, capable of dissolving many gases, liquids and solids, so that natural water contains variable amounts of dissolved minerals and organic matter. Its purest form in nature occurs as rain, while distilled water represents the purest form resulting from processing.