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magnesite

(Encyclopedia)magnesite măgˈnəsīt [key], mineral, magnesium carbonate, MgCO3, white, yellow, or gray in color. It originates through the alteration of olivine or of serpentine by waters carrying carbon dioxide;...

electrolyte

(Encyclopedia)electrolyte ĭlĕkˈtrəlītˌ [key], electrical conductor in which current is carried by ions rather than by free electrons (as in a metal). Electrolytes include water solutions of acids, bases, or s...

depilatory

(Encyclopedia)depilatory dĭpĭlˈətôrˌē [key], substance used to remove hair. In preparing hides for tanning, lime is the chief depilatory. For the removal of superfluous hair from the human body, metal sulfid...

Davy, Sir Humphry

(Encyclopedia)Davy, Sir Humphry, 1778–1829, English chemist and physicist. The son of a woodcarver, he received his early education at Truro and was apprenticed (1795) to a surgeon-apothecary at Penzance. While d...

Rochelle salt

(Encyclopedia)Rochelle salt, colorless to blue-white orthorhombic crystalline salt with a saline, cooling taste. It is also called Seignette salt after Pierre Seignette, an apothecary of La Rochelle, France, who wa...

benzoic acid

(Encyclopedia)benzoic acid bĕnzōˈĭk [key], C6H5CO2H, crystalline solid organic acid that melts at 122℃ and boils at 249℃. It is the simplest aromatic carboxylic acid (see aryl group and carboxyl group). In ...

Carrel, Alexis

(Encyclopedia)Carrel, Alexis kärĕlˈ, kə– [key], 1873–1944, American surgeon and experimental biologist, b. near Lyons, France, M.D. Univ. of Lyons, 1900. Coming to the United States in 1905, he joined the s...

Bordeaux mixture

(Encyclopedia)Bordeaux mixture bôrdōˈ [key], fungicide consisting of cupric sulfate and lime in water. Its fungicidal activity is associated with the slow formation of copper compounds, the ultimate toxicant bei...

airglow

(Encyclopedia)airglow, faint diffuse illumination of the sky originating in the upper atmosphere. Although it occurs at all times of day throughout the upper atmosphere, it is most typically visible to an observer ...

Ketterle, Wolfgang

(Encyclopedia)Ketterle, Wolfgang, 1957–, German physicist, Ph.D. Max Planck Institute for Quantum Optics, Garching, Germany, 1986. He has been a professor at Massachusetts Institute of Technology since 1990. Kett...