What is dry ice an example of?
A Sublimation
B. Codensation
C. Draporation
D. Deposition
The correct answer and explanation is:
The correct answer is A. Sublimation.
Dry ice is solid carbon dioxide (CO2), and it undergoes a process called sublimation. Sublimation is the transition of a substance directly from the solid phase to the gas phase, skipping the liquid phase. This happens when the temperature and pressure conditions allow the solid to vaporize without first melting into a liquid.
Dry ice does not melt into a liquid but instead “disappears” or evaporates directly into carbon dioxide gas when exposed to normal atmospheric pressure. This process occurs at temperatures below -78.5°C (-109.3°F). The phenomenon of sublimation is distinct because most substances, when heated, transition from solid to liquid and then to gas. However, dry ice moves directly from solid to gas without becoming a liquid.
This characteristic of dry ice is what makes it so useful for cooling and creating fog effects. It’s often used in situations where refrigeration is needed without the risk of liquid water forming, as it does not leave any liquid residue behind. It’s also used in science experiments and theatrical performances for creating dramatic fog effects.
Sublimation differs from the other processes listed. Condensation (B) is the process of a gas turning into a liquid, which is the opposite of sublimation. Draporation (C) is not a recognized scientific term, and Deposition (D) is the opposite of sublimation. Deposition occurs when a gas transitions directly to a solid without becoming a liquid. Dry ice’s behavior clearly falls under sublimation.