After dry ice is put into water, the temperature of water will sublimate dry ice and produce CO2 bubbles. When the CO2 in the water reaches saturation (1 volume of water can dissolve about 1 volume of CO2), the CO2 that continues to be generated will be removed from the water. We see the white gas around us because the dry ice in the water will absorb a lot of heat, which will lead to the rapid drop of local temperature and make the water vapor in the surrounding air liquefy into small water droplets.
Dry ice is solid carbon dioxide, which is condensed into colorless liquid under the pressure of 6250.5498 kPa, and then rapidly solidified under high pressure.
Carbon dioxide is a colorless and odorless gas, which naturally exists in the air. Although the content of carbon dioxide in air is relatively small (about 0.03% by volume), it is one of the most important gases we know.
Dry ice is volatile and sublimated into non-toxic and odorless gas carbon dioxide, which is 600-800 times larger than the solid volume, so dry ice cannot be stored in containers with completely sealed volume, such as plastic bottles, and it is easy to explode when mixed with liquids.
Extended data
Use of dry ice:
1, dry ice will absorb heat when sublimating, thus reducing the ambient temperature. Therefore, dry ice is often used as a refrigerant. Spraying dry ice in the air by plane can liquefy the water vapor in the air, thus forming artificial rainfall.
2. Dry ice is also used in food industry. Adding dry ice to wine, cocktail or beverage is cool and delicious when drinking, and the cup is full of smoke, which is very pleasant. When making ice cream, dry ice is added, which is not easy to melt, and is especially suitable for cold storage of takeaway ice cream.
Seafood dishes made by star-rated hotels and restaurants, with dry ice, can produce white smoke landscape and improve the banquet level. Lobster, crab, shark's fin and other seafood are frozen and refrigerated. Dry ice will not melt into water, and it is cleaner and cleaner than storing ice.
3. Dry ice is used in the field of refrigerated transportation. Cryopreservation, medical use and transportation of special drugs such as plasma and vaccines. Long-distance and short-distance transportation of electronic cryogenic materials and precision components.
4. Dry ice is widely used in entertainment fields, such as stage, theater, film and television, wedding and celebration, and some programs are made of dry ice.
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