Gold parting will not dissolve gold, nearly pure gold (very close to 99.5% pure) will be left behind after the reaction is complete. After removing the solid gold other elements like silver and copper may be extracted from the liquid. To get the gold to a very high level of purity (999 fine gold) it is sometimes processed further with aqua regia to effectively remove all the impurities. Aqua regia was also used for parting. It was made by adding sal ammoniac to nitric acid which produced a mixture of hydrochloric acid and nitric acid. This acid dissolved the gold to a
Acetoacetic acid colour change is graded by eye. The test does not measure β-hydroxybutyrate, the most abundant ketone in the body; during treatment of ketoacidosis β-hydroxybutyrate is converted to acetoacetate so the test is not useful after treatment begins and may be falsely low at diagnosis. Similar tests are used in dairy cows to test for ketosis. Acetoacetic acid Acetoacetic acid (also diacetic acid) is the organic compound with the formula CHCOCHCOOH. It is the simplest beta-keto acid group, and like other members of this class, it is unstable. The methyl and ethyl esters, which are quite stable, are produced on a