Mixing a specific quantity of dry ice with an equal mass of water at 80°C results in a final mixture temperature of__________________?
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Answer: B. 0°C
Explanation
Dry ice absorbs substantial latent heat from the warm water while sublimating directly into carbon dioxide gas. The warm water loses thermal energy continuously until its temperature drops to the freezing point of water. The final thermal equilibrium of the mixture settles exactly at zero degrees Celsius during the phase change. Dry ice is solid carbon dioxide maintained at an extremely cold sublimation temperature of minus seventy-eight degrees. Water possesses a high specific heat capacity and a latent heat of fusion of three hundred thirty-four kilojoules per kilogram. Mixing extreme cryogens with room-temperature liquids creates rapid heat transfer accompanied by significant phase transitions.
Maintaining eighty degrees Celsius ignores the massive heat sink effect of sublimating dry ice within the liquid. A final temperature of forty or sixty degrees implies insufficient heat transfer between the two unequal thermal masses. A twenty degree Celsius outcome fails to account for the total latent heat required to transition the system.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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