Popular science | Wide in the application of silver compounds

Source: Visual China

Silver, the element 47 element is the precious metal we are familiar with, second only to gold. It has a history of more than 4,000 years of mining, refining, and use. It has been made into jewelry and appliances for transactions. my country's archeologists have found "gold and silver errors" inlaid on the surface of the appliance (a pattern with gold and silver silk) inlaid on the surface of the appliance. At the same time, silver is also used as a medium for commodity exchange -currency, such as ancient silver ingots and silver dollars in ancient my country. Silver is not just as simple as precious metals in our lives.

Traditionally, we always think that silver is the "second important" metal, and the silver medal is awarded the second place in the competition. In fact, silver exceeds gold in some aspects. For example, it is the best conductivity in the world and the brightest metal under the standard. In the junior high school chemistry classes, the single -quality silver replaced by copper in the nitrate silver, the white white flowers are reminiscent of the "fire tree silver flower".

Silver has the characteristics of sterilization and anti -virus. As early as more than 300 BC, when the Macedonian kingdom was in the east, most soldiers died of illness due to tropical dysentery, but the emperor and officers were spared due to the use of silver tableware. In 659 AD, the earliest silver cream used to repair the teeth in my country appeared in China. The silver coin invested in the wishing pool also has the effect of removing the bacteria. Modern technology allows people to gradually realize that silver can decompose trace silver ions in water. This silver ions can absorb microorganisms in water at a low concentration, causing the enzymes of microorganisms to lose their breath, thereby killing microorganisms, and one -meter millions of silver can purify 1 kg of water, and the sterilization capacity is amazing. Modern medicine made silver and silver alloy into various human tissues, such as fabric materials for teeth and surgery, long -term catheter, etc., which can prevent bacteria from invasion of infection.

Ancient forensic doctors in my country also knew how to use the "silver needle autopsy" to determine whether the deceased died of poisoning or whether the food was poisonous, but it could only test the poison caused by frost. Because silver can react with arsenic in the cream to generate silver oxide black precipitation to test poison, the effect of silver needles for other types of poisons is still limited.

Modern craftsmanship makes silver in various forms, and nano -silver is one of them. Nano is a type of length, and nano silver refers to silver particles with a diameter of 1 to 100 nanometers. It can be used as a colored glass, which is used as a biotechnology and biological engineering, textile engineering, water treatment, and some consumer products, such as washing machines and refrigerators as antibacterial agents.

Modern chemical research has a lot of applications containing silver compounds: adding alkali to the silver solution to get silver oxide precipitation. The generated silver oxide can be used as the positive pole of the silver -zinc butt battery; For generics, you can generate chloride to silver nitrate. The glass electrodes used in the industry to manufacture the pH value and measure the potential can provide more accurate data. The silver bromide still depends on the light -sensitive silver -based silver -made silver film with stable glue matrix. Among them, there is better lithographic bromide; if iodized salt is added to the silver nitrate solution Artificial rainfall can be performed in the cloud layer; reaction with glucose and silver ammonia solution can restore metal silver, and can be used to make the plating of the mirror and the inner surface of the glass Christmas jewelry.

(The author is a chemical teacher in Wuhan City, Hubei Province, a member of the science science group of Wuhan scientists)

Source: Popular Science Times Author: Song Dan

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