Dry ice is:
Question: What is dry ice?
Dry ice is a form of carbon dioxide in its solid state. When carbon dioxide gas is cooled at high pressure, it solidifies to form dry ice. It is commonly used as a cooling agent because it sublimates at -78.5°C (-109.3°F), transitioning directly from a solid to a gas without becoming liquid, which is why it is called "dry" ice. This property makes it ideal for use in situations where a dry cooling environment is needed.
Option | Description |
---|---|
Lead monoxide | Not dry ice; it is a compound of lead and oxygen. |
Silicon carbide | Not dry ice; it is a compound of silicon and carbon. |
Solid carbon dioxide | This is dry ice; the solid form of CO2. |
Glacier ice | Not dry ice; this is naturally occurring frozen water. |
Correct Answer: Solid carbon dioxide
Dry ice is the solid form of carbon dioxide (CO₂), which is a colorless, odorless gas that naturally occurs in the Earth's atmosphere. Unlike regular ice, which is made of water, dry ice has a unique property—it does not melt into a liquid. Instead, it undergoes a process called sublimation, in which it transitions directly from a solid to a gas without passing through a liquid phase. This occurs at a temperature of approximately -78.5°C (-109.3°F).
This distinctive characteristic of dry ice makes it particularly useful in a variety of applications, from preserving perishable goods during transportation to creating fog effects in entertainment.
For example, it is often used in stage productions and haunted houses to create a smoky, fog-like atmosphere. Furthermore, since dry ice sublimates so rapidly, it can be dangerous if not handled properly. It releases carbon dioxide gas, which can cause suffocation in enclosed spaces, so it is essential to use it in well-ventilated areas. Despite this risk, dry ice remains an important tool due to its ability to keep things frozen at much lower temperatures than regular ice can provide.
Which among the following is a supercooled liquid?