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acetone

(Encyclopedia)acetone prōˈpənōn [key], CH3COCH3, colorless, flammable liquid. Acetone melts at −94.8℃ and boils at 56.2℃. It is the simplest aliphatic ketone. Acetone is widely used in industry as a solve...

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 ...

Carothers, Wallace Hume

(Encyclopedia)Carothers, Wallace Hume kərŭᵺˈərz [key], 1896–1937, American chemist, b. Burlington, Iowa. He received his doctorate at the Univ. of Illinois in 1924, then taught organic chemistry there and a...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

mite

(Encyclopedia)mite, small, often microscopic arachnid that belongs to several orders in the subclass Acari (or Acarina), to which the tick also belongs; mites and ticks are related to the spiders. The unsegmented m...

Pará, state, Brazil

(Encyclopedia)Pará pəräˈ [key], state (1996 pop. 5,552,783), 474,896 sq mi (1,229,981 sq km), N Brazil, in the lower Amazon River basin bordering on the Guianas and the Atlantic Ocean. Belém is the capital. Mo...

hyperinsulinism

(Encyclopedia)hyperinsulinism, presence in the system of an above-normal amount of insulin, the substance secreted by the pancreas and needed by the body to utilize sugar. An increased amount of insulin in the body...

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. ...

nutrition

(Encyclopedia)nutrition, study of the materials that nourish an organism and of the manner in which the separate components are used for maintenance, repair, growth, and reproduction. Nutrition is achieved in vario...

chemical industry

(Encyclopedia)chemical industry, the business of using chemical reactions to turn raw materials, such as coal, oil, and salt, into a variety of products. During the 19th and 20th cent. technological advances in the...