Amalgam (chemistry) with copper. A nitric acid solution of salts under investigation is applied to a piece of copper foil, and any mercury ions present will leave spots of silvery-coloured amalgam. Silver ions leave similar spots but are easily washed away, making this a means of distinguishing silver from mercury. The redox reaction involved where mercury oxidizes the copper is: Dental amalgam has been studied and is generally considered to be safe for humans, though the validity of some studies and their conclusions have been questioned. Amalgam (chemistry) An amalgam is an alloy of mercury with another metal, which may be a
Chirality (chemistry) derived from the interaction of chiral materials with polarized light. In a solution, the (−)-form, or levorotatory form, of an optical isomer rotates the plane of a beam of linearly polarized light counterclockwise. The (+)-form, or dextrorotatory form, of an optical isomer does the opposite. The rotation of light is measured using a polarimeter and is expressed as the optical rotation. The rotation of plane polarized light by chiral substances was first observed by Jean-Baptiste Biot in 1815, and gained considerable importance in the sugar industry, analytical chemistry, and pharmaceuticals. Louis Pasteur deduced in 1848 that this phenomenon has a