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pyridine

(Encyclopedia)pyridine ăzˈēn [key], C5H5N, colorless, flammable, toxic liquid with a putrid odor. It melts at −42℃ and boils at 115.5℃. Chemically, it is a heterocyclic aromatic tertiary amine (see under a...

oscilloscope

(Encyclopedia)oscilloscope əsĭlˈəskōpˌ [key], electronic device used to produce visual displays corresponding to electrical signals. Displays of such nonelectrical phenomena as the variations of a sound's int...

mercury, chemical element

(Encyclopedia)mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842℃; b.p. 356.58℃; sp. gr. 13.55...

elephant bird

(Encyclopedia)elephant bird, extinct, flightless bird of the family Aepyornithidae. Once native to the island of Madagascar, these gigantic birds may have survived until as late as 1649. Today, they are known only ...

apheresis

(Encyclopedia)apheresis hēˌməfĕrˈəsĭs [key], any procedure in which blood is drawn from a donor or patient and a component (platelets, plasma, or white blood cells) is separated out, the remaining blood comp...

mustard gas

(Encyclopedia)mustard gas, chemical compound used as a poison gas in World War I. The burning sensation it causes on contact with the skin is similar to that caused by oil from black mustard seeds. The compound is ...

nitrobenzene

(Encyclopedia)nitrobenzene, C6H5NO2, very poisonous, flammable, pale yellow, liquid aromatic compound with an odor like that of bitter almonds. It is sometimes called oil of mirbane or nitrobenzol. Nitrobenzene mel...

nitroglycerin

(Encyclopedia)nitroglycerin nīˌtrōglĭsˈərĭn [key], C3H5N3O9, colorless, oily, highly explosive liquid. It is the nitric acid triester of glycerol and is more correctly called glycerol trinitrate. It is insol...

aerosol dispenser

(Encyclopedia)aerosol dispenser, device designed to produce a fine spray of liquid or solid particles that can be suspended in a gas such as the atmosphere. The dispenser commonly consists of a container that holds...

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...