Dry ice with your hands. Formula of dry ice

Dry ice is a very necessary and indispensable thing. It can be used to maintain a constant low temperature, cooling of any household items in conditions of high ambient temperatures. It is widely used in industry, as a cooler for tanks and refrigerators, in cooking while creating culinary masterpieces. But it is not always possible to purchase dry ice when it is so necessary.

There are several options for how to get or make dry ice with your own hands in a traditional kitchen.

What is dry ice?

In fact, this substance has nothing to do with frozen water, that is, with ordinary ice, except for the ability to maintain low temperatures or cool anything. The formula of dry ice is the same as that of carbon dioxide - CO2. As a matter of fact, this is gas, which is converted into a solid aggregate state, bypassing the liquid phase.

With this chemical compound, we meet every day. It is contained in the exhaled air. When you buy carbonated water or a drink in the store, you have often seen how bubbles of carbon dioxide shoot out when you open the bottle.

A large amount of it is emitted with transport exhaust gases and is contained in the ambient air. Due to its ability to inhibit combustion processes, it is used in the production of fire extinguishers for domestic and industrial purposes. Carbon dioxide is used by plants to carry out the process of photosynthesis. But isolating it from the environment is a very laborious and costly process.

Preparation of dry ice

No matter how absurd this may sound, dry ice is a gas. On an industrial scale, it is produced by cooling carbon dioxide at high pressure. At home, these processes can not be carried out, because Requires specialized equipment and the creation of certain conditions. Nevertheless, some options for how to get dry ice with your own hands, still exist.

Dry ice from a fire extinguisher

Initially, to obtain dry ice you will need a fire extinguisher, a dense cloth bag and wire or an adhesive tape.

To the base of the bell of the fire extinguisher, it is necessary to attach the existing bag in such a way that no holes remain. To be sure, it is better to seal it with tape or tape. Hermeticity plays a very important role here. Next, it is worth carefully removing the fuse from the handle of the extinguisher and releasing several jets of carbon dioxide by pressing the drain valve. Thus, the carbon dioxide in the fire extinguisher's container under pressure does not have time to cool down and accumulates in the bag in the form of powder or crystals. In order that it does not evaporate, it must be placed in an airtight container or bag and tightly closed.

In the same way, you can get dry ice with your hands from a carbon dioxide cylinder, which is used for welding. The cylinder valve should be opened very slowly, because the gas pressure in it is very high. It should be extremely careful not to let carbon dioxide enter the skin of the hands and face, as this can cause frostbite.

Dry ice from a test tube

The following method can be useful if you have access to the simplest laboratory equipment. If this is not possible, then at home it can be used without any problems. This will require a fire extinguisher, safety glasses, baking soda, vinegar and a strong plastic bag.

Dry ice can be obtained in small quantities with the help of a few simple laboratory experiments. To do this, you need to get carbon dioxide by mixing soda, which is available in any kitchen, and table vinegar. The structure and formula of dry ice determine its gaseous state. For the convenience of collecting carbon dioxide, this experiment should be carried out in a glass tube with a gas outlet tube. The end of the tube should be placed in water. The rising bubbles of carbon dioxide will fill another tube, displacing water. To get more carbon dioxide, they should fill the existing plastic bag.

In order to obtain dry ice, the temperature of which is very low, it will take carbon dioxide and create certain conditions. This can not be done in a simple laboratory or at home. Gas from the package can be used as a substrate or substrate to increase the amount of dry ice. But it must be sharply cooled. To do this, the gas bag must be secured to the same source of dry ice, a fire extinguisher or a can, and to release several jets into the package. Thus, dry ice will cool carbon dioxide from the package, which will contribute to its precipitation in the solid phase.

Use of dry ice

The temperature of dry ice is so low that it will be enough to make home-made ice cream or other desserts that require cooling or quick freezing. It can also be used to cool food and drinks on the outing, but avoid contact with moisture. Dry ice in water begins to pass into the gaseous state, which is accompanied by abundant release of heavy thick smoke.

Safety precautions

Before using a fire extinguisher for your experiments, you should make sure that it is carbon dioxide. On its body there should be a special information marking. The use of other types of fire extinguishers will not allow to obtain the expected result and can be dangerous.

Do not try to get dry ice from cylinders for a gas or pneumatic gun. The opening of these objects is extremely dangerous and can lead to unpredictable consequences. When working with a fire extinguisher, use protective goggles and gloves to prevent cold carbon dioxide from entering the mucous membranes.

The carbon dioxide fire extinguisher is best purchased at the appropriate store. Then you can be sure that it is completely working. Dry ice from it can be obtained, periodically refueling it, for example, in the fire department.