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This page provides supplementary chemical data on caffeine. Caffeine ... Melting point: 227 to 228 °C (441 to 442 °F; 500 to 501 K) (anhydrous)
Salicylic acid is an organic compound with the formula HOC 6 H 4 COOH. [3] A colorless (or white), bitter-tasting solid, it is a precursor to and a metabolite of acetylsalicylic acid (aspirin). [3]
The diagnosis of poisoning usually involves measurement of plasma salicylate, the active metabolite of aspirin, by automated spectrophotometric methods. Plasma salicylate levels in general range from 30 to 100 mg/L after usual therapeutic doses, 50–300 mg/L in people taking high doses and 700–1400 mg/L following acute overdose.
Salicylamide is used in combination with both aspirin and caffeine in the over-the-counter pain remedy PainAid. It was also an ingredient in the over-the-counter pain remedy BC Powder but was removed from the formulation in 2009, and Excedrin used the ingredient from 1960 to 1980 in conjunction with aspirin , acetaminophen , and caffeine .
Pure anhydrous caffeine is a bitter-tasting, white, odorless powder with a melting point of 235–238 °C. [ 7 ] [ 8 ] Caffeine is moderately soluble in water at room temperature (2 g/100 mL), but quickly soluble in boiling water (66 g/100 mL). [ 197 ]
The Gmelin rare earths handbook lists 1522 °C and 1550 °C as two melting points given in the literature, the most recent reference [Handbook on the chemistry and physics of rare earths, vol.12 (1989)] is given with 1529 °C.
Salicin is found in the bark of and leaves of willows, poplars and various other plants. [5] Derivates are found in castoreum.Salicin from meadowsweet was used in the synthesis of aspirin (acetylsalicylic acid), [6] in 1899 by scientists at Bayer.
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa.