1 and palladium (palladium) are one of the rarest precious metals in the world, and the element symbol Pd is one of the platinum group elements. Palladium has high purity, similar appearance to platinum, silvery white metallic luster in natural state and never fades. Palladium has high temperature resistance, corrosion resistance, wear resistance and ductility. In terms of purity, rarity and durability, platinum can be used instead, which is an ideal material for making jewelry and inlaid gems. Palladium, together with platinum, gold and silver, is one of the international precious metal spot and futures trading varieties, which was once higher than platinum in history. In addition, palladium is also a widely used catalyst, from petrochemical industry to medical treatment, from automobiles to watches.
2. Palladium is chemically stable, insoluble in hydrofluoric acid and resistant to phosphoric acid, perchloric acid, hydrochloric acid and cold sulfuric acid. Sodium hydroxide, sodium carbonate and sodium peroxide dissolved in aqua regia, hot concentrated sulfuric acid and concentrated nitric acid have corrosive effects on palladium. _N Gray seeds lose their luster. When the temperature is about 400℃, oxides will be produced on the surface. When heated to 800℃ in room temperature air and humid environment, palladium oxide film will be formed on the surface of palladium. Palladium has a natural pure white luster like platinum, and its color is bright. It also looks like platinum, but compared with platinum, the price of palladium is lower. Because palladium has some unique physical and chemical characteristics, it is more difficult to process jewelry than platinum, and the requirements for all links are very high. Palladium is often associated with platinum, and its output is less than platinum. In mineral classification, platinum group elements belong to natural platinum subgroup, including natural element minerals such as iridium, rhodium, palladium and platinum. There is a wide range of isomorphic substitution between them, thus forming a series of isomorphic mixed crystals. These elements have great similarities in physical and chemical properties. Especially palladium and platinum, two precious metals, are very much like brothers. The metallurgical properties of these two metals are very similar, because they are also rare and have similar uses, and they often replace each other in various applications.