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potassium nitrate

(Encyclopedia)potassium nitrate, chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also ...

enthalpy

(Encyclopedia)enthalpy ĕnˈthălpē [key], measure of the heat content of a chemical or physical system; it is a quantity derived from the heat and work relations studied in thermodynamics. As a system changes fro...

sulfonic acid

(Encyclopedia)sulfonic acid səlfŏnˈĭk [key], organic compound containing the functional group RSO2OH, which consists of a sulfur atom, S, bonded to a carbon atom that may be part of a large aliphatic or aromati...

alizarin

(Encyclopedia)alizarin əlĭzˈərĭn [key], or 1,2-dihydroxyanthraquinone, mordant vegetable dye obtained originally from the root of the madder plant (Rubia tinctorum), in which it occurs as a glucoside. The term...

damask

(Encyclopedia)damask dămˈəsk [key] [from Damascus], fabric of silk, wool, linen, cotton, or synthetic fibers, with a pattern formed by the weaving; e.g., the ground may be in twill weave, and the contrasting des...

ferrous sulfate

(Encyclopedia)ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeSO4·7...

Geoffroy, Étienne François

(Encyclopedia)Geoffroy, Étienne François ātyĕnˈ fräNswäˈ zhôfrwäˈ [key], 1672–1731, French physician and chemist, also known as Geoffroy the Elder. He became a pharmacist in 1694 and received an M.D. a...

molecular modeling

(Encyclopedia)molecular modeling, the computer simulation, by various means, of chemical structures or processes. Special computer-graphics programs can display three-dimensional images of molecular structures and ...

tubercle

(Encyclopedia)tubercle to͞oˈbərkyo͞olˌ [key] [Lat.,=little swelling], small, usually solid, nodule or prominence. In anatomy the term is applied to natural prominences in certain muscles, to nerve nuclei of th...

zinc oxide

(Encyclopedia)zinc oxide, chemical compound, ZnO, that is nearly insoluble in water but soluble in acids or alkalies. It occurs as white hexagonal crystals or a white powder commonly known as zinc white. Zinc white...