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Question
Give scientific reasons for the following:
Bottled drinks are cooled more effectively when surrounded by lumps of ice than by cold water at 0°.
Solution 1
Lumps of ice cool better than cold water because each gram of ice requires additional 80 calories of heat to get converted into water. Hence, cooling capacity of lumps of ice is more than cold water.
Solution 2
Every 1 kg of ice at 0°C absorbs 336,000 J of heat energy to form water at 0°C. As ice can extract 336,000 J of heat energy, more than water at 0°C, therefore it cools the bottled drinks more effectively.
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