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nitro group

(Encyclopedia)nitro group, in chemistry, functional group that consists of a nitrogen atom joined to two oxygen atoms. Compounds that contain a nitro group, e.g., picric acid and trinitrotoluene (TNT), are called n...

Bosch, Carl

(Encyclopedia)Bosch, Carl, 1874–1940, German chemist and engineer, Ph.D. Univ. of Leipzig, 1898. In 1899, Bosch began working as a chemist for BASF, which merged with six other German chemical firms to become I. ...

sodium nitrate

(Encyclopedia)sodium nitrate, chemical compound, NaNO3, a colorless, odorless crystalline compound that closely resembles potassium nitrate (saltpeter or niter) in appearance and chemical properties. It is soluble ...

energy

(Encyclopedia)CE5 Relations between potential energy (PE) and kinetic energy (KE) for a swinging pendulum energy, in physics, the ability or capacity to do work or to produce change. Forms of energy include hea...

N

(Encyclopedia)N, 14th letter of the alphabet. It is a usual symbol for a voiced alveolar (or dental) nasal, as in the English not. The diagraph ng represents a different sound, a voiced velar nasal, as in the Engli...

H

(Encyclopedia)H, 8th letter of the alphabet. It is a usual symbol for a glottal spirant, murmured (as in the English house) or voiceless (as in the English herb). In some Greek alphabets eta, the long e, had this f...

barograph

(Encyclopedia)barograph, instrument used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the v...

S

(Encyclopedia)S, 19th letter of the alphabet, representing the common sibilant, voiceless in spur, voiced in rose. Its Greek equivalent is sigma. In former times the nonterminal s was written or printed much like a...

B

(Encyclopedia)B, second letter of the alphabet. Its Greek correspondent is named beta. It is a usual symbol for a voiced bilabial stop. In musical notation it is used to represent a note in the scale. In chemistry ...

V

(Encyclopedia)V, 22d letter of the alphabet (see U). It is a usual symbol for a voiced labiodental spirant, as in the English vat. In Roman numerals it corresponds to Arabic 5. In chemistry V is the symbol of the e...