Dry ice is put into the plate. When the dish is served, the dry ice in the dish will turn into white gas when it comes into contact with normal temperature air. Dry ice is solid carbon dioxide, which condenses into colorless liquid under the pressure of 6250.5498 kPa, and then rapidly solidifies under low pressure. The history of dry ice can be traced back to 1823. Faraday and Derby in Britain liquefied carbon dioxide for the first time, and then Quirrell in Germany successfully produced solid carbon dioxide in 1834. But it was only used for research at that time and was not widely used.

Dry ice is mainly made in two forms, either a piece weighing more than 50 pounds (22.7 kilograms) or a small piece of dry ice the size of a grain of rice to a larger particle size. Dry ice does not melt, but sublimates, that is, when the temperature rises and the solid begins to dissipate, the solid directly becomes gas (bypassing the liquid state). This unusual feature will lead to smoke effect, and dry ice seems to smoke when sublimed. Therefore, dry ice is usually used to simulate fog or smoke.

Dry ice itself is not poisonous, but the solid surface is so cold that it can't be touched without gloves. In addition, although gas is stable and inert, it is heavier than air and can be concentrated in low-lying areas or enclosed spaces. When the concentration of carbon dioxide in the air exceeds 5%, carbon dioxide will become toxic. Therefore, any place where dry ice is used must be well ventilated.

The appearance of dry ice

French chemist Thilorier was the first person to record the appearance of solid dry ice. 1835, he opened a cylinder filled with a large amount of liquid carbon dioxide and observed that it was liquid. A large amount of water evaporates, leaving solid dry ice cubes at the bottom of the container.

In the next 60 years, dry ice was observed in the laboratories of various universities, but it was not used in any practical application. Even today, anyone can use a metal bottle filled with liquid carbon dioxide (such as a CO2 fire extinguisher) to open the valve and observe the gas cloud ejected, some of which will turn into dry ice snowflakes, and they will be curious about it.

first time

1897, a British patent was awarded to HerbertSamuelElworthy, a doctor of the British Army Medical Team. He needs to mix soda with whisky. Liquid carbon dioxide works well, but metal bottles are too heavy for short trips. A 100 pound steel cylinder contains only 50 pounds of carbon dioxide. He prefers to make soda water with solid dry ice. Unfortunately, dry ice didn't take long, because it sublimated into gas before it was used up. Since then, very little dry ice has been used for this patent purpose. Now, some doctors use dry ice to remove warts.

formal application

1925 At the beginning of this year, American DryIce Company began to produce dry ice, but they had no customers. Their first customer was SchraffsStores in 1926, a candy store selling Eskimo pie ice cream and other items. Schraffs tries to keep the ice cream cold so that customers can eat it at home instead of in the store. Dry ice is the best solution. Before dry ice, salt is added to water and then frozen. This cold "salt water ice" will keep the ice cream frozen when it is distributed to retail stores. But the molten salt water ice is corrosive, and the salt water will flow out and the weight will increase. Therefore, dry ice becomes an ideal solution. By 1927, many ice cream manufacturers, including Breyers ice cream, have used American DryIceCorporation to produce and store ice cream.