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ammonium group
(Encyclopedia)ammonium group, in chemistry, a positively charged nitrogen atom joined by single bonds to four other atoms or groups. The simplest ammonium group, NH4+, is formed by protonation of ammonia, NH3, e.g....uremia
(Encyclopedia)uremia yo͝orēˈmēə [key], condition resulting from advanced stages of kidney failure in which urea and other nitrogen-containing wastes are found in the blood. Uremia can be caused by NSAIDs (nons...Boussingault, Jean Baptiste Joseph Dieudonné
(Encyclopedia)Boussingault, Jean Baptiste Joseph Dieudonné zhäN bätēstˈ zhôzĕfˈ dyödônāˈ bo͞osăNgōˈ [key], 1802–87, French agricultural chemist. He was professor of chemistry at Lyons and later pr...sulfuric acid
(Encyclopedia)sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Although sulfuric acid is now one of the most widely used c...titanium
(Encyclopedia)titanium tītāˈnēəm, tĭ– [key] [from Titan], metallic chemical element; symbol Ti; at. no. 22; at. wt. 47.867; m.p. 1,675℃; b.p. 3,260℃; sp. gr. 4.54 at 20℃; valence +2, +3, or +4. Titani...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...tetraethyl lead
(Encyclopedia)tetraethyl lead tĕtˌrəĕthˈəl [key], (C2H5)4Pb, viscous, colorless, poisonous liquid. It is an organometallic compound prepared by reacting ethyl chloride with a sodium-lead alloy. When added to ...pulse, in botany
(Encyclopedia) CE5 Sweet pea, Lathyrus odoratus, a member of the pulse family pulse, in botany, common name for members of the Fabaceae (Leguminosae), a large plant family, called also the pea, or legume, family...mineral water
(Encyclopedia)mineral water, spring water containing various mineral salts, especially the carbonates, chlorides, phosphates, silicates, sulfides, and sulfates of calcium, iron, lithium, magnesium, potassium, sodiu...electronegativity
(Encyclopedia)electronegativity ĭlĕkˌtrōnĕgətĭvˈətē [key], in chemistry, tendency for an atom to attract a pair of electrons that it shares with another atom (see chemical bond). For example, the molecule...Browse by Subject
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