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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...

carbonate

(Encyclopedia)carbonate kärˈbənātˌ, –nət [key], chemical compound containing the carbonate radical or ion, CO3−2. Most familiar carbonates are salts that are formed by reacting an inorganic base (e.g., a ...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

cyclamate

(Encyclopedia)cyclamate sīˌkləmātˌ, –mət [key], any member of a group of salts of cyclamic acid (cyclohexanesulfamic acid). The sodium and calcium salts were commonly used as artificial sweeteners until 196...

lapis lazuli

(Encyclopedia)lapis lazuli lăpˈĭs lăzˈo͝olē [key], gem, deep blue, violet, or greenish blue in color and usually flecked with yellow iron pyrites. It is composed of lazurite, a complex sodium aluminum silica...

cryolite

(Encyclopedia)cryolite or kryolite both: krīˈəlītˌ [key] [Gr.,=frost stone], mineral usually pure white or colorless but sometimes tinted in shades of pink, brown, or even black and having a luster like that o...

antimony

(Encyclopedia)antimony ănˈtĭmōˌnē [key] [Lat. antimoneum], semimetallic chemical element; symbol Sb [Lat. stibium,=a mark]; at. no. 51; at. wt. 121.760; m.p. 630.74℃; b.p. 1,750℃; sp. gr. (metallic form) ...

soap

(Encyclopedia)soap, a cleansing agent. It cleanses by lowering the surface tension of water, by emulsifying grease, and by absorbing dirt into the foam. Ancient peoples are believed to have employed wood ashes and ...

molecule

(Encyclopedia)molecule mŏlˈəkyo͞ol [key] [New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, a...

dynamite

(Encyclopedia)dynamite, explosive made from nitroglycerin and an inert, porous filler such as wood pulp, sawdust, kieselguhr, or some other absorbent material. The proportions vary in different kinds of dynamite; o...