Post memes/jokes in /r/chemistrymemes and /r/chemistryjokes. Any such posts will be deleted.Īsk education and jobs questions in the current weekly topic. If you're looking for a more concentrated, advanced discussion of chemistry topics among professionals and grad students, check out /r/Chempros.īefore asking "What chemical is this?" see this chart. Click here for the OSHA chemical data site and here for a multicompany MSDS aggregate search. Gold chloride and gold chloride tetrahydrate are other names for this acid. These catalysts show a higher amount and production rate of hydrogen via a water-splitting reaction. The light brown solid product (COPN-1) was dried by using a vacuum oven at 75 ☌ for 3 hours. Furthermore, this chemical is used as a purification step for the gold. Gold(III) chloride hydrate can be used to prepare TiO 2-supported Au-based photocatalyst by deposition-precipitation with urea. After distillation and crystallization, we. If you spill/injure yourself contact medical professionals and read the MSDS, do not post to this reddit. After 3 hours, the brown precipitate was obtained and this precipitate was washed thrice with acetone (15 mL), then thrice with distilled water (15 mL). Chloroauric acid Preparation: Dissolve the pure gold in aqua regia (or hydrochloric acid saturated by chlorine gas). Yes links to blogs, images, videos, comics, and infographics are okay especially if they are on your personal website. Introduction Gold nanoparticles (Au NPs) have potential applications in medicine, catalysis, electronics and photonics due to their unique chemical and physical properties compared with their bulk counterpart. No physorg, sciencedaily, or other press release aggregator spam! If a caption or explanation is included this helps, but please use your discretion.īefore asking about chemical drawing/illustration programs, look at your school's IT/software website and see if they provide an institutional license of ChemDraw (hint: if they have a chemistry department, they will) Likewise, simple pictures of uninteresting and garden variety chemistry-related things are not appreciated. No memes, rage comics, image macros, reaction gifs, or other "zero-content" material. However, academic discussions on pharmaceutical chemistry and the science of explosives are permitted. Solutions of Au(III) are not overly toxic, but due to the ease at which it can be reduced, solutions of Au(III) should be reduced to the metal before disposal.Rules: Violating a rule will result in a ban.Īsk homework, exam, lab, and other undergraduate-level questions at ChemicalForums otherwise it will be deleted.ĭiscussions on illicit drug synthesis, bomb making, and other illegal activities are not allowed and will lead to a ban. Appropriate equations are: Au +3HNOX3 +4HCl AuClX4X +3NOX2 +HX3OX+ +2HX2O A u + 3 H N O X 3 + 4 H C l A u C l X 4 X + 3 N O X 2 + H X 3 O X + + 2 H X 2 O. In addition, gold may be dissolved by the free chlorine present in aqua regia. Shouldn't be stored for long periods of time.ĭue the price of gold, all efforts should obviously be taken to avoid any wastage. The gold dissolves to become chloroauric acid. The usual precautions when dealing with strong acids should be in place, as not only is chloroauric acid a strong acid, but unless dried, solutions may contain traces of either of the two corrosive mineral acids used to make it. The mechanism that allows gold to dissolve involves the nitric acid acting as an oxidizing agent to produce trivalent gold ions (Au 3+) which then combine with the chlorine ions to form tetrachloroaurate ions (AuCl 4-). The solid is very hygroscopic, so calculating accurate yields based on weight is difficult. This results in an orange-yellow solution that can be dried in a desiccator. Because of this, it is generally only available from suppliers at a very high purity, driving up the price further.Ĭhloroauric acid is prepared by dissolving gold in aqua regia, a mix of concentrated hydrochloric and nitric acids. of chloroauric acid, this substance was so completely adsorbed that it could not be. While hygroscopic, solutions and the solid are stable at standard conditions.Īs expected, chloroauric acid is expensive and often only marketed for high end chemistry applications. of the precipitated gold was shaken with a solution containing a few mg. I have also used dry lye alone to precipitate gold hydroxide from a clean Chloroauric acid solution and the results was a nearly black powder that settled fast and melted into a shiny gold button. Like other Au(III) compounds, reaction with gaseous or solutions of ammonia will precipitate the dangerously explosive ' fulminating gold', with explosive properties similar to silver acetylide. Oxalic acid and sodium metabisulfite are often used in this way to produce the pure metal from dissolved scrap gold. Many reducing agents reduce chloroauric acid to metallic gold, which falls out of solution as a yellow powder.
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