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hydroxyl group

(Encyclopedia)hydroxyl group hīdrŏkˈsĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a single bond to a hydrogen atom. An alcohol is formed when a hydroxyl group is joined by ...

alkali

(Encyclopedia)alkali ălˈkəlī [key] [Arab., al-gili=ashes of saltwort], hydroxide of an alkali metal. Alkalies are readily soluble in water and form strongly basic solutions with a characteristic acrid taste. Th...

crucible

(Encyclopedia)crucible, vessel in which a substance is heated to a high temperature, as for fusing or calcining. The necessary properties of a crucible are that it maintain its mechanical strength and rigidity at h...

photoengraving

(Encyclopedia)photoengraving, photomechanical process in the graphic arts, used principally for reproducing illustrations. The subject is photographed, and the image is recorded on a sensitized metal plate, which i...

Roseville

(Encyclopedia)Roseville. 1 City (1990 pop. 44,685), Placer co., N central Calif., a suburb of Sacramento in the foothills of the Sierra; inc. 1909. Marked by rapid growth in the late 20th cent., Roseville is in an ...

niello

(Encyclopedia)niello nēĕlˈō [key] [Ital. from Latin nigellus=blackish], black metallic alloy of sulfur, copper, silver, and usually lead, used as an inlay on engraved metal. The metal surface is brushed with a ...

voltaic cell

(Encyclopedia)voltaic cell, a simple device with which chemical energy is converted into electrical energy. Two dissimilar metals (e.g., copper and zinc) are immersed in an electrolyte (e.g., a dissolved sulfate). ...

Erlanger

(Encyclopedia)Erlanger, city (2020 pop. 19,611), Kenton co., N central Ky.; inc. 1897. Its manufactures include chemicals, sheet metal, medical supplies, and sports a...

Southbridge

(Encyclopedia)Southbridge, town (1990 pop. 17,816), Worcester co., S Mass., on the Quinebaug River; settled 1730, inc. 1816. Chemicals, tools, metal products, and clothing are manufactured. ...

thulium

(Encyclopedia)thulium tho͞oˈlēəm [key] [from Thule, an ancient name for Scandinavia], metallic chemical element; symbol Tm; at. no. 69; at. wt. 168.93421; m.p. about 1,545℃; b.p. 1,947℃; sp. gr. 9.3; valenc...