“Dry ice” refers to________________?
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Answer: C. Solid carbon dioxide
Explanation
Dry ice is the widely accepted commercial name for solid carbon dioxide. It transitions directly from solid to gas at room temperature without melting. Handling solid carbon dioxide requires insulated gloves due to its extremely cold temperature. Solid carbon dioxide sublimes at minus seventy-eight point five degrees Celsius at atmospheric pressure. It leaves no liquid residue behind when it vaporizes, earning the name dry ice. Industrial carbon dioxide gas is compressed and frozen to manufacture solid blocks.
Food delivery services use dry ice to keep perishable items frozen during long transit. Theater productions create heavy fog effects by submerging dry ice in warm water. Scientific laboratories use solid carbon dioxide for low-temperature cooling baths. Moisture free ice is simply frozen water and does not sublime like carbon dioxide. Solid helium requires near absolute zero temperatures and extreme pressures to form. Stating none of these is wrong because solid carbon dioxide is the correct definition.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
- Difficulty
- medium
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