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suspension, in chemistry

(Encyclopedia)suspension, in chemistry, mixture of two substances, one of which is finely divided and dispersed in the other. Common suspensions include sand in water, fine soot or dust in air, and droplets of oil ...

sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

valence, in chemistry

(Encyclopedia)valence, combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound. Atoms are c...

sol, in chemistry

(Encyclopedia)sol, in chemistry: see colloid.

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

resonance, in chemistry

(Encyclopedia)resonance, in chemistry: see chemical bond. ...

Ion, in Greek mythology

(Encyclopedia)Ion: see Creusa (1.)

Sörensen, Sören Peter Lauritz

(Encyclopedia)Sörensen, Sören Peter Lauritz söˈrən pēˈtər louˈrēts söˈrənsən [key], 1868–1939, Danish biochemist. In 1899 he received a Ph.D. degree in Copenhagen. Sörensen was director of chemistr...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

MacKinnon, Roderick

(Encyclopedia)MacKinnon, Roderick, 1956–, American biochemist, b. Burlington, Mass., M.D. Tufts Univ., 1982. MacKinnon was on the faculty at Harvard Medical School from 1989–96 and has been a professor at the H...