HYDROFLUORIC
Hy`dro*flu*or"ic, a. Etym: [Hydro-, 2 + fluoric.] (Chem.)
Defn: Pertaining to, or containing, hydrogen and fluorine; fluohydric; as, hydrofluoric acid. Hydrofluoric acid (Chem.), a colorless, mobile, volatile liquid, HF, very corrosive in its action, and having a strong, pungent, suffocating odor. It is produced by the action of sulphuric acid on fluorite, and is usually collected as a solution in water. It attacks all silicates, as glass or porcelain, is the agent employed in etching glass, and is preserved only in vessels of platinum, lead, caoutchouc, or gutta-percha.
HYDROFLUOSILICATE
Hy`dro*flu`o*sil"i*cate, n. (Chem.)
Defn: A salt of hydrofluosilic acid; a silicofluoride. See
Silicofluoride.
HYDROFLUOSILICIC
Hy`dro*flu`o*si*lic"ic, a. Etym: [Hydro-, 2 + fluorine + silicic.]
(Chem.)
Defn: Pertaining to, or denoting, a compound consisting of a double fluoride of hydrogen and silicon; silicofluoric. See Silicofluoric.
HYDROGALVANIC
Hy`dro*gal*van"ic, a. Etym: [Hydro-, 1 + galvanic.]
Defn: Pertaining to, produced by, or consisting of, electricity evolved by the action or use of fluids; as, hydrogalvanic currents. [R.]
HYDROGEN Hy"dro*gen, n. Etym: [Hydro-, 1 + -gen: cf. F. hydrogène. So called because water is generated by its combustion. See Hydra.] (Chem.)
Defn: A gaseous element, colorless, tasteless, and odorless, the lightest known substance, being fourteen and a half times lighter than air (hence its use in filling balloons), and over eleven thousand times lighter than water. It is very abundant, being an ingredient of water and of many other substances, especially those of animal or vegetable origin. It may by produced in many ways, but is chiefly obtained by the action of acids (as sulphuric) on metals, as zinc, iron, etc. It is very inflammable, and is an ingredient of coal gas and water gas. It is standard of chemical equivalents or combining weights, and also of valence, being the typical monad. Symbol H. Atomic weight 1.