Ice Cubes & Liquid Water - Thermodynamics

AI Thread Summary
The discussion revolves around a thermodynamics problem involving the mixing of ice cubes and warm water. The participant initially attempted to calculate the final temperature of the mixture using heat transfer principles but arrived at an incorrect answer of 21°C. They realized they neglected to account for the latent heat required for the ice to melt. Acknowledgment of this oversight led to a commitment to reattempt the problem correctly. The conversation highlights the importance of considering latent heat in thermodynamic calculations.
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Homework Statement



Four ice cubes at exactly 0 \ { }^{\circ} \text{C} with a total mass of 53.5 \ \text{g} are combined with 115 \ \text{g} of water at 75 \ { }^{\circ} \text{C} in an insulated container. If no heat is lost to the surroundings, what will be the final temperature of the mixture?

Homework Equations



No specific formulas. Just basic thermodynamics, as explained in the solution.

The Attempt at a Solution



Magnitude of heat gained by Ice cubes = Magnitude of heat lost by Water
4m_{\text{one ice cube}}c_{\text{ice}}(T'-T_{\text{0-ice}})=m_{\text{water}}c_{\text{water}}(T_{\text{0-water}}-T')
From here, I used the numbers in my book and got the wrong answer [below]. :(
21 Degrees Celsius
 
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You mean you end with water and ice at 21°C?
 
Yes, Sir, but that's my answer, not the correct one.
 
Sigh.

Have you ever seen ice at 21°C?
 
Ah! I guess I forgot the latent heat. That was obliviously silly. Thanks for helping me through my silliness! I'll re-try the problem once I can and, hopefully, I'll get it right this time around. :) Sorry and thank you, again.
 
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