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Why does ice sink in ethanol and oil?
Because the density of ice is higher, at least for ethanol. The density of ice is 0.917 grams per cubic centimeter, that of water is 1. So ice, being less dense than water will float. The density of ethanol is 0.789 so ice will sink in it. The density of different oils varies from 0.91 to 0.93, close to that of ice. So in some oils the ice will float and in others the ice will sink.
(published on 06/22/09)
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