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acid anhydride

(Encyclopedia)acid anhydride ănhīˈdrīd, –drəd [key], chemical compound that reacts with water to form an acid (see acids and bases). Anhydrides of inorganic acids are usually oxides of nonmetallic elements. ...

mining

(Encyclopedia)mining, extraction of solid mineral resources from the earth. These resources include ores, which contain commercially valuable amounts of metals, such as iron and aluminum; precious stones, such as d...

Caen

(Encyclopedia)Caen käN [key], city, capital of Calvados dept., N France, in Normandy, on the Orne River. I...

emetic

(Encyclopedia)emetic əmĕtˈĭk [key], substance that produces vomiting. Direct, or gastric, emetics, which act directly on the stomach, include syrup of ipecac, sulfate of zinc or copper, alum, ammonium carbonate...

hand sanitizer

(Encyclopedia)hand sanitizer or hand rub, substance used to clean and sanitize the hands, especially when soap is not available. Hand sanitizers, introduced commercially in the late 1980s, are available as liquids,...

water glass

(Encyclopedia)water glass or soluble glass, colorless, transparent, glasslike substance available commercially as a powder or as a transparent, viscous solution in water. Chemically it is sodium silicate, potassium...

hotbed

(Encyclopedia)hotbed, low, glass-covered frame structure for starting tender plants. It differs from a cold frame only in that the soil is heated—either artificially as by underground electric wiring or steampipe...

distillation

(Encyclopedia)distillation, process used to separate the substances composing a mixture. It involves a change of state, as of liquid to gas, and subsequent condensation. The process was probably first used in the p...

lanolin

(Encyclopedia)lanolin, greasy, yellow substance extracted from wool. When purified, it is used as a base for ointments and creams, as a lubricant, and in finishing and preserving leather. It is also a constituent o...

potassium chloride

(Encyclopedia)potassium chloride, chemical compound, KCl, a colorless or white, cubic, crystalline compound that closely resembles common salt (sodium chloride). It is soluble in water, alcohol, and alkalies. Potas...