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phosphorus

(Encyclopedia)phosphorus fŏsˈfərəs [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 +5. So...

match

(Encyclopedia)match, small stick whose chemically coated tip bursts into flame when struck on a rough surface. Before the introduction of the match, fire was made by friction methods using the stick and the groove,...

phosphoric acid

(Encyclopedia)phosphoric acid, any one of three chemical compounds made up of phosphorus, oxygen, and hydrogen (see acids and bases). The most common, orthophosphoric acid, H3PO4, is usually simply called phosphori...

adenosine triphosphate

(Encyclopedia) CE5 Adenosine triphosphate (ATP) adenosine triphosphate (ATP) ədĕnˈəsēn trīˌfŏsˈfāt [key], organic compound composed of adenine, the sugar ribose, and three phosphate groups. ATP serves ...

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...

rickets

(Encyclopedia)rickets or rachitis rəkīˈtĭs [key], bone disease caused by a deficiency of vitamin D or calcium. Essential in regulating calcium and phosphorus absorption by the body, vitamin D can be formed in t...

guano

(Encyclopedia)guano gwäˈnō [key], dried excrement of sea birds and bats found principally on the coastal islands of Peru, Africa, Chile, and the West Indies. It contains about 6% phosphorus, 9% nitrogen, 2% pota...

bone meal

(Encyclopedia)bone meal, finely ground bone used as a fertilizer for its content of phosphate and nitrogen (about 23%–30% available phosphate and 2%–4% nitrogen); it is an expensive form of phosphoric acid when...

superphosphate

(Encyclopedia)superphosphate or superphosphate of lime, Ca(H2PO4)2, is a compound produced by treating rock phosphate with sulfuric acid or phosphoric acid, or a mixture of the two. It is the principal carrier of p...
 

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