Warming ice, melting ice, and cooling water

Tutoring chemistry, heat flow between hot and cold substances might be studied. The tutor mentions a reflection about water and ice.

Today, while thawing chicken breasts in water, I wondered how much water would be needed to supply the necessary heat to thaw them.

Interestingly, solid ice heats up twice as easily as liquid water cools: it takes 2.09kJ/kg to warm ice one degree Celsius (say, for instance, from -4C to -3C), but liquid water releases 4.18kJ/kg for each degree Celsius it cools.

Melting ice is a more demanding proposition: it takes about 160 times as much heat to melt a kilogram of ice as to heat it one degree Celsius (once again, from -4C to -3C, for example). In particular, it takes 334kJ/kg to melt ice.

Source:

Hebden, James. Chemistry: Theory and Problems, Book Two. Toronto: McGraw-Hill Ryerson, 1980.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

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