On February 10, when Ms. Xu's family in Luzhou, Zhejiang, she accidentally found a ring on the chicken feet.
5 thoughts on “What substances can corrode gold?”
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On February 10, when Ms. Xu's family in Luzhou, Zhejiang, she accidentally found a ring on the chicken feet.
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We know that gold itself is not corroded, so how does the rust on the gold coin come from? Zhou Weirong told reporters that in order to solve this fan, they selected 5 more typical gold coins (Kirin gold coins, Guanyin gold coins, muddy gold coins each, and panda gold coins) from the collection of gold coins. There are two energy spectrum detection methods, scanning electron microscope detection on both samples on both sides of the gold coin sample (the former can only detect elements above sodium in the element cycle table, and the latter can detect carbon oxygen nitrogen Wait for light elements), and match the facial distribution analysis of each element. The rust spots on the surface of the gold coin can be divided into five types of material composition: high silver rust spots, silicate spots, iron chromium oxide spots or rubbing marks, organic spots and soluble salt spots. The main manifestations of rust. The five spots on gold coins can be divided into two categories. The first three types are the same type, which belongs to the inorganic object of water. The latter two are the same category, which belong to organic matter and inorganic salts dissolved in water. The nature of these two types of spots is different, and its sources are different. The three types of spots in the first category should be pollutant or mold drops that are admitted to the blank material or landed on the currency table during the suppression process. When the gold coins are stamped, the gold coins are pressed on the surface of the gold coin. Among them, the first high -silver spots should be metal silver at first, and later the effect of oxide in the environment formed chemicals such as oxide. The aging decomposition of packaging materials and the harmful gases in the air have a direct promotion effect on the growth of this rust spots. ; The second type of silicate is obviously pollutants such as dust. The surface of the gold coin is embedded during stamping. Unlike the first spots, this spots themselves will not directly oxidize and diffuse, but because it is a coin surface defect, it is easy to become a easily become a flawed. The corrosion target area, and the existence of this spots also affects the smoothness of the gold coins; the third type of iron chromium oxide spot or rubbing marks is a small particle tiny gold coin that is dropped off by the stamping mold. form. The two types of spots in the second category should be caused by adhesion before and after the stamping molding of gold coins. During the sorting, packaging, distribution, ornamental and viewing of gold coins, the sweat on the hands and the organic droplets floating in the air may form such spots on the surface of the gold coin.
There are usually four types of corrosive liquids used to corrode the metal, which are acidic, alkaline, oxidation type, and coordination type;
are acidic, mostly hydrochloric acid, and a small number of cases can be used for corrosion of iron, lead, aluminum, and Most of the common metals such as manganese;
alkaline, mostly use sodium hydroxide or potassium hydroxide, can corrode aluminum, silicon (silicon industry and metallurgy), etc. This is the most type, because most metals are passivated or inertia, so most of them use nitric acid, king water and other substances to corrode, and more oxidized under acidic conditions. It can be used to corrode titanium, chromium, gold, silver, copper , Platinum and other materials that are not easy to chemically process;
This also has a kind of corrosive liquid that is contributed. In fact, it is to reduce the electrode potential of the metal. In the metal that is easy to match in copper, gold, 锡, tin
Gold is a rare metal and has good chemical stability. Generally, it is difficult to react with other substances. However, chemical reactions can still occur under high temperature and strong oxidative conditions. For example, disinfectant, nitrate water, etc. can corrode gold.
Nothing can have corrosion effect on anything, but it is not significant.
The corrosion of essential oil on gold is small, and it can be ignored. After all, gold is one of the best metals. The most corrosive is individual hydrochloric acid, sulfuric acid, and nitric acid, which can corrode gold under certain conditions.
Well, if you want to corrode gold, there are many things, such as that strong acid and strong alkali can be corroded metal. As long as he is metal, he can re -test through that strong acid and alkali. Class can be re -examined