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phosphorus
(Encyclopedia)phosphorus fŏsˈfərəs [key] [Gr.,=light-bearing], nonmetallic chemical element; symbol P; at. no. 15; at. wt. 30.97376; m.p. 44.1℃; b.p. about 280℃; sp. gr. 1.82 at 20℃; valence −3, +3, or ...oxygen
(Encyclopedia)oxygen, gaseous chemical element; symbol O; at. no. 8; interval in which at. wt. ranges 15.99903–15.99977; m.p. −218.4℃; b.p. −182.962℃; density 1.429 grams per liter at STP; valence −2. T...Democritus
(Encyclopedia)Democritus dĭmŏkˈrĭtəs [key], c.460–c.370 b.c., Greek philosopher of Abdera; pupil of Leucippus. His theory of the nature of the physical world was the most radical and scientific attempted up ...hydrogen peroxide
(Encyclopedia)hydrogen peroxide, chemical compound, H2O2, a colorless, syrupy liquid that is a strong oxidizing agent and, in water solution, a weak acid. It is miscible with cold water and is soluble in alcohol an...hypothalamus
(Encyclopedia)hypothalamus hīˌpəthălˈəməs [key], an important supervisory center in the brain, rich in ganglia, nerve fibers, and synaptic connections. It is composed of several sections called nuclei, each ...Sidoarjo mudflow
(Encyclopedia)Sidoarjo mudflow or Lusi [Lumpur Sidoarjo, Bahasa Indonesia, = Sidoarjo mud], mud volcano, Sidoarjo regency, central East Java prov., Indonesia, 20 mi (30 km) S of Surabaya. In May, 2006, a hot mu...sleep apnea
(Encyclopedia)sleep apnea, episodes of interrupted breathing during sleep. Obstructive sleep apnea is a common disorder in which relaxation of muscles in the throat repeatedly close off the airway during sleep; the...smelt
(Encyclopedia)smelt, common name for a small, slender fish of the family Osmeridae. Most species are marine, but some ascend freshwater streams to spawn and others are landlocked in lakes. The rainbow or American s...silicone
(Encyclopedia)silicone, polymer in which atoms of silicon and oxygen alternate in a chain; various organic radicals, such as the methyl group, CH3, are bound to the silicon atoms. Silicones, which are unusually sta...potassium chloride
(Encyclopedia)potassium chloride, chemical compound, KCl, a colorless or white, cubic, crystalline compound that closely resembles common salt (sodium chloride). It is soluble in water, alcohol, and alkalies. Potas...Browse by Subject
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