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delirium tremens

(Encyclopedia)delirium tremens trēˈmənz, trĕmˈənz [key], hallucinatory episodes that may occur during withdrawal from chronic alcoholism, popularly known as the DTs. An episode of delirium tremens is usually ...

sodium hydrogen carbonate

(Encyclopedia)sodium hydrogen carbonate: see sodium bicarbonate. ...

sodium tetraborate decahydrate

(Encyclopedia)sodium tetraborate decahydrate: see borax. ...

formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

benzaldehyde

(Encyclopedia)benzaldehyde bĕnˌzēnkärˈbənəl [key], C6H5CHO, colorless liquid aldehyde with a characteristic almond odor. It boils at 180℃, is soluble in ethanol, but is insoluble in water. It is formed by ...

chlorine

(Encyclopedia)chlorine klōrˈēn, klôrˈ– [key] [Gr.,=green], gaseous chemical element; symbol Cl; at. no. 17; interval in which at. wt. ranges 35.446–35.457; m.p. −100.98℃; b.p. −34.6℃; density 3.2 g...

Graham, Thomas

(Encyclopedia)Graham, Thomas, 1805–69, Scottish chemist, best known for research in diffusion in both gases and liquids that led to his formulation of Graham's law. His discovery that certain substances (e.g., gl...

carbonated beverage

(Encyclopedia)carbonated beverage, an effervescent drink that releases carbon dioxide under conditions of normal atmospheric pressure. Carbonation may occur naturally in spring water that has absorbed carbon dioxid...

potassium

(Encyclopedia)potassium pətăsˈēəm [key], a metallic chemical element; symbol K [Lat. kalium=alkali]; at. no. 19; at. wt. 39.0983; m.p. 63.25℃; b.p. 760℃; sp. gr. .862 at 20℃; valence +1. Potassium is a s...

X-ray crystallography

(Encyclopedia)X-ray crystallography, the study of crystal structures through X-ray diffraction techniques. When an X-ray beam bombards a crystalline lattice in a given orientation, the beam is scattered in a defini...