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hydrogen-ion concentration

(Encyclopedia)hydrogen-ion concentration: see pH.

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

concentration

(Encyclopedia)concentration, in chemistry, measure of the relative proportions of two or more quantities in a mixture. The concentration of a solute is very important in studying chemical reactions because it deter...

ion, in chemistry

(Encyclopedia)ion, atom or group of atoms having a net electric charge. Ionization has many applications. Vapor lamps and fluorescent lamps take advantage of the light given off when positive ions recombine with ...

complex ion

(Encyclopedia)complex ion, charged molecular aggregate (see ion), consisting of a metallic atom or ion to which is attached one or more electron-donating molecules. In some complex ions, such as sulfate, SO4−2, t...

concentration camp

(Encyclopedia)concentration camp, a detention site outside the normal prison system created for military or political purposes to confine, terrorize, and, in some cases, kill civilians. The term was first used to d...

pH

(Encyclopedia)pH, range of numbers expressing the relative acidity or alkalinity of a solution. In general, pH values range from 0 to 14. The pH of a neutral solution, i.e., one which is neither acidic nor alkaline...

hydrogen fluoride

(Encyclopedia)hydrogen fluoride, chemical compound, HF, a colorless, fuming liquid or colorless gas that boils at 19.54℃. It is miscible with water and is soluble in benzene, toluene, and concentrated sulfuric ac...

hydrogen sulfide

(Encyclopedia)hydrogen sulfide, chemical compound, H2S, a colorless, extremely poisonous gas that has a very disagreeable odor, much like that of rotten eggs. It is slightly soluble in water and is soluble in carbo...