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peroxide

(Encyclopedia)peroxide pərŏkˈsīd [key], chemical compound containing two oxygen atoms, each of which is bonded to the other and to a radical or some element other than oxygen; e.g., in hydrogen peroxide, H2O2, ...

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 ...

photochemistry

(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...

vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

Prussian blue

(Encyclopedia)Prussian blue, pigment widely used for laundry bluing, in dyeing compounds, and in the manufacture of inks and paints. Several varieties are known, one of which consists of the chemical compound ferri...

Zhupanovsky

(Encyclopedia)Zhupanovsky, compound volcano, 9,705 ft (2,958 m), on the Kamchatka peninsula, Kamchatka Territory, Russia, c.40 mi (65 km) N of Petropavlovsk. Zhupanovsky consists of four stratovolcanoes along a rid...

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 ...

amino group

(Encyclopedia)amino group, in chemistry, functional group that consists of a nitrogen atom attached by single bonds to hydrogen atoms, alkyl groups, aryl groups, or a combination of these three. An organic compound...

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....

smaltite

(Encyclopedia)smaltite smôlˈtīt [key], opaque tin-white to steel-gray mineral of the pyrite group, a compound of cobalt and arsenic. It occurs in massive form, occasionally in crystals (cubes) of the isometric s...