How did the first peoples know which foods were safe to eat? Excellent question! Food historians make educated guesses based on ancient records and modern practices.
When water freezes its entropy decreases. This does not violate the second law of thermodynamics. The second law does not say that entropy can never decrease anywhere. It just says that the total entropy of the universe can never decrease.he entropy increases whenever heat flows from a hot object to a cold object. It increases when ice melts, water is heated, water boils, water evaporates. The entropy increases when a gas flows from a container under high pressure into a region of lower pressure.
If water was most dense at its freezing point (0 Â°C) then it would sink to the bottom, freezing a body of water from the bottom up, killing all of the organisms living within it 29. Instead, this property ensures that the bottom of a body of water will remain at least 4Â°C, and thus unfrozen 30.