1 By convention a normal lens on a 35mm film camera (and thus a full-frame EOS digital SLR) has a focal length of 50mm or so. 2  A lens with a focal length of 35mm is considered ânormalâ for a cropped-frame EF-S camera.
Aspirin. One of the best known aromatic acetates is acetylsalicylic acid, or aspirin, which is prepared by the esterification of the phenolic hydroxyl group of salicylic acid. Aspirin possesses a number of properties that make it the most often recommended drug.
2-acetoxybenzoic acid 2-(acetyloxy)benzoic acid salicylic acid acetate acetylsalicylic acid aspirin C9H8O4 MW: 180.15 odorless crystals (6 polymorphs) pKa = 3.48 LD50 (mice) = 1.1 g/kg In 1950, Aspirin was listed in the Guinness Book of World Records as the best-selling pain-reliever in history.