Dry ice is solid carbon dioxide (CO₂).
Why is it called "Dry Ice"?
Unlike regular ice (water ice), dry ice doesn't melt into a liquid. Instead, it undergoes a process called sublimation, transforming directly from a solid to a gas. This is why it's called "dry"—it doesn't leave behind any wet residue as it disappears.
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Sublimation: This is the phase transition where a substance changes directly from a solid to a gas without passing through an intermediate liquid phase. Dry ice's sublimation at standard atmospheric pressure and temperature is a key characteristic.
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Cooling Agent: Dry ice is used as a powerful cooling agent because of its extremely low temperature (-78.5°C or -109.3°F). Its sublimation also facilitates cooling because it absorbs heat from the surrounding environment as it transitions to a gas.
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Applications: Dry ice finds applications in various fields including:
- Food preservation
- Special effects (fog)
- Medical applications
- Industrial cleaning
Several sources confirm this: Byjus.com, LearnCBSE.in, and various other educational websites all state that dry ice is the solid form of carbon dioxide and that the term "dry" refers to its sublimation process. Wikipedia also corroborates this information, detailing the process of sublimation and its applications.
