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formula weight

(Encyclopedia)formula weight, in chemistry, a quantity computed by multiplying the atomic weight (in atomic mass units) of each element in a formula by the number of atoms of that element present in the formula, an...

nitrate

(Encyclopedia)nitrate, chemical compound containing the nitrate (NO3) radical. Nitrates are salts or esters of nitric acid, HNO3, formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radic...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...

cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

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...

water gas

(Encyclopedia)water gas, colorless poisonous gas that burns with an intensely hot, bluish (nearly colorless) flame. The gas is a mixture of carbon monoxide and hydrogen with very small amounts of other gases, e.g.,...

parathyroid glands

(Encyclopedia)parathyroid glands pârˌəthīˈroid [key], four small endocrine bodies, located behind the thyroid gland, that govern calcium and phosphorus metabolism. These four masses of tissue (each about the s...

isomorphism

(Encyclopedia)isomorphism īˌsəmôrˈfĭzəm [key], of minerals, similarity of crystal structure between two or more distinct substances. Sodium nitrate and calcium sulfate are isomorphous, as are the sulfates of...

anion

(Encyclopedia)anion ănˈīˌən [key], atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduc...

Bratianu

(Encyclopedia)Bratianu –nô [key], Romanian family. Ion Bratianu, 1821–91, was prominent in the Revolution of 1848 and helped to secure (1866) the election of Prince Carol of Hohenzollern-Sigmaringen (Carol I o...