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Winthrop, John, 1606–76, colonial governor in America

(Encyclopedia)Winthrop, John, 1606–76, colonial governor in America, b. Groton, Suffolk, England; oldest son of John Winthrop (1588–1649). He was educated at Trinity College, Dublin, became a lawyer, and emigra...

cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

hassium

(Encyclopedia)hassium hăsˈēəm, häsˈ– [key], artificially produced radioactive chemical element; symbol Hs; at. no. 108; mass number of most stable isotope 277; m.p., b.p., sp. gr., and valence unknown. Situ...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

Fehling's solution

(Encyclopedia)Fehling's solution fāˈlĭngz [key], deep-blue, alkaline solution used to test for the presence of aldehydes (e.g., formaldehyde, HCHO) or other compounds that contain the aldehyde functional group, ...

cytochrome

(Encyclopedia)cytochrome sīˈtəkrōmˌ [key], protein containing heme (see coenzyme) that participates in the phase of biochemical respiration called oxidative phosphorylation. Cytochromes act as carriers of hydr...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

Benedict's solution

(Encyclopedia)Benedict's solution, deep-blue alkaline solution used to test for the presence of the aldehyde functional group, −CHO. The substance to be tested is heated with Benedict's solution; formation of a b...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...