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ammonium chloride

(Encyclopedia)ammonium chloride əmōˈnēəm klôrˈīd [key], chemical compound, NH4Cl, a white or colorless, odorless, water-soluble, cubic crystalline salt with a biting taste, commonly known as sal ammoniac. I...

sodium chloride

(Encyclopedia)sodium chloride, NaCl, common salt. Salt is important in many ways. It is an essential part of the diet of both humans and animals and is a part of most animal fluids, such as blood, sweat, and te...

palladium, chemical element

(Encyclopedia)palladium [Gr. Pallas, goddess of wisdom], metallic chemical element; symbol Pd; at. no. 46; at. wt. 106.42; m.p. 1,554℃; b.p. 2,970℃; sp. gr. 12.02 at 20℃; valence +2, +3, or +4. Palladium is a...

peroxide

(Encyclopedia)peroxide pərŏkˈsīd [key], chemical compound containing two oxygen atoms, each of which is bonded to the other and to a radical or some element other than oxygen; e.g., in hydrogen peroxide, H2O2, ...

mercury, chemical element

(Encyclopedia)mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842℃; b.p. 356.58℃; sp. gr. 13.55...

hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

mercuric chloride

(Encyclopedia)mercuric chloride or mercury (II) chloride, chemical compound, HgCl2, a white powder of colorless rhombohedral crystals, somewhat soluble in water. It is also called bichloride of mercury or corrosive...

cobalt, chemical element

(Encyclopedia)cobalt, metallic chemical element; symbol Co; at. no. 27; at. wt. 58.9332; m.p. 1,495℃; b.p. about 2,870℃; sp. gr. 8.9 at 20℃; valence +2 or +3. Cobalt is a silver-white, lustrous, hard, brittle...

hydrogen cyanide

(Encyclopedia)hydrogen cyanide, HCN, colorless, volatile, and extremely poisonous chemical compound whose vapors have a bitter almond odor. It melts at −14℃ and boils at 26℃. It is miscible in all proportions...

ferrous sulfate

(Encyclopedia)ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeSO4·7...