Dextrin

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Dextrin, amorphous, soluble carbohydrate, (C6H10O5)n, produced by the action on starch paste of acids, heat, or enzymes such as diatase. The first product formed in this reaction is soluble starch, which in turn hydrolyzes to form dextrin. Dextrin is prepared commercially by moistening potato starch with weak nitric acid and then drying and heating the mass at 110° C (230° F). Dextrin is used in the manufacture of beer and as a substitute for gum arabic in printing cotton fabrics. It is also used commercially as an adhesive.

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. Beryllium, symbol Be, gray, brittle metallic element, with an atomic number of 4. It is in group 2 (or IIa) of the periodic table (see Periodic Law ). Beryllium was named for its chief mineral, beryl , an aluminum beryllium silicate. It was discovered as an oxide, now known as beryllia, in 1797 by French chemist Louis Nicolas Vauquelin. The free element was first isolated in 1828 independently by Friedrich Wöhler and Antonine Alexandre Brutus Bussy. Because the soluble compounds are sweet-tasting, the new element was first called glucinium, a reference to the sugar glucose . PROPERTIES AND OCCURRENCE Beryllium, one of the alkaline earth metals , ranks about 51st in natural abundance among the elements in the earth's crust. Its atomic weight is 9.012. Beryllium melts at about 1287° C (about 2349° F), boils at about 3000° C (about 5432° F), and has a specific gravity of 1.85. Beryllium has a high strength per unit weight. It tarnishes only slightly in air, becoming covered with a ...
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Electricity and Magnetism

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