How Much Energy Does Ice Release When Cooled in a Freezer?

AI Thread Summary
The discussion focuses on calculating the thermal energy released by a 3.0 kg block of ice as it cools from -5.0°C to -40.0°C. The initial calculation used the specific heat of water, resulting in an incorrect value of -439530 J. It is clarified that the specific heat capacity of ice is different from that of water, which is essential for accurate calculations. The correct specific heat for ice should be applied to find the energy released, leading to the expected answer of approximately 2.2 x 10^5 J. Understanding the difference in specific heat capacities is crucial for solving thermal energy problems involving ice.
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Homework Statement



A 3.0kg block of ice made in a fridge has an initial temp. of -5.0\circC. It
is then moved to a much colder freezer. how much thermal energy is released by the ice as it cools to -40.0\circC?

Homework Equations


EH = mc\DeltaT
for water, c = 4186 J/kg/\circC


The Attempt at a Solution


EH = mc\DeltaT
EH = (3.0kg)(4186 J/kg/\circC)(-40.0\circC - -5.0\circC)
= -439530 J
but the answer should be 2.2 x 10^5 J
help?
 
Last edited:
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The specific heat of ice is different from that of water.
 

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