Rearrangements wonât occur if the initially formed carbocation is the most thermodynamically stable out of all the possible isomers. For example, if you use t-butyl bromide in a Friedel-Crafts alkylation, it will not rearrange, since the t-butyl c... This page may be out of date. Save your draft before refreshing this page.
Platinum was first used for minting coins in Spanish-colonized America. Following the discovery of platinum in gold rocks, the Spaniards were unable to use it for a long time because they had no technology for processing this metal.latinum was first used for minting coins in Spanish-colonized America. Following the discovery of platinum in gold rocks, the Spaniards were unable to use it for a long time because they had no technology for processing this metal.
Platinum is an attractive silvery white metal with a melting point of 1,774 deg C, a boiling point of 3,827 deg C and a density of 21.45 g/cu cm at room temperature. It has a coefficient of thermal expansion close to that of soda lime silica glass and is consequently used to make sealed electrodes in soft glass systems.