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paint

(Encyclopedia)paint, mixture of a pigment and a binding medium, usually thinned with a solvent to form a liquid vehicle. The term includes lacquer, portland cement paint, printing ink, calcimine, and whitewash. Pai...

uric acid

(Encyclopedia)uric acid yo͝orˈĭk [key], white, odorless, tasteless crystalline substance formed as a result of purine degradation in man, other primates, dalmatians, birds, snakes, and lizards. The last three gr...

nitrous oxide

(Encyclopedia)nitrous oxide or nitrogen (I) oxide, chemical compound, N2O, a colorless gas with a sweetish taste and odor. Its density is 1.977 grams per liter at STP. It is soluble in water, alcohol, ether, and ot...

sodium hydroxide

(Encyclopedia)sodium hydroxide, chemical compound, NaOH, a white crystalline substance that readily absorbs carbon dioxide and moisture from the air. It is very soluble in water, alcohol, and glycerin. It is a caus...

silver chloride

(Encyclopedia)silver chloride, chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate (“h...

catabolism

(Encyclopedia)catabolism kətăbˈəlĭzˌəm [key], subdivision of metabolism involving all degradative chemical reactions in the living cell. Large polymeric molecules such as polysaccharides, nucleic acids, and ...

cation

(Encyclopedia)cation kătˌīˈən [key], atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed from a metal by oxi...

Darwin, Erasmus

(Encyclopedia)Darwin, Erasmus, 1731–1802, English physician and poet. During most of his life he practiced medicine in Lichfield and cultivated a botanical garden. He was a prominent member of the Lichfield liter...

chernozem

(Encyclopedia)chernozem chĕrˈnəzĕmˌ [key] or black earth, variety of soil rich in organic matter in the form of humus. It is generally a modified type of loess. True chernozem is black in color, but there are ...

naphtha

(Encyclopedia)naphtha năpˈthə, năfˈ– [key], term usually restricted to a class of colorless, volatile, flammable liquid hydrocarbon mixtures. Obtained as one of the more volatile fractions in the fractional ...