Gold parting instead of copper. One part pure gold is alloyed with three parts Sterling silver (inquarting). The resulting six karat (6K) gold can then be parted with dilute nitric acid (one part 68-70% nitric acid to one part DISTILLED water). With the karat gold this low (6K), and over medium high heat, the dilute nitric acid will dissolve the Sterling silver (and other base metals in the karat gold) starting on the outside surface of the 6K gold alloy, working its way into the gold alloy, forming a honeycomb structure as it works its way into the metals. Since nitric acid
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