How much ice is melted in a Carnot engine using a hot and cold reservoir?

AI Thread Summary
In a Carnot engine scenario, 6437 J of heat is input, and the efficiency is calculated as 26.8%, leading to a work output that allows for heat transfer to the cold reservoir. The remaining heat delivered to the cold reservoir is 73.2% of the input energy. Using the heat of fusion for water, the amount of ice melted is determined to be 0.0141 kg. The calculations involve applying the efficiency and the heat transfer equations correctly. The discussion concludes with the successful determination of the ice melted based on the provided data.
rlc
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Homework Statement


A Carnot engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. When 6437 J of heat is put into the engine and the engine produces work, how many kilograms of ice in the tub are melted due to the heat delivered to the cold reservoir?

Homework Equations


Q=m*(deltaHf)
efficiency=1-(T_cold/T_hot)

The Attempt at a Solution


Searching online, I found those equations but nothing is working for me.
With the efficiency, I found:
1-(273/373)=0.268
And the heat of fusion for water is 3.34E5 J/kg

What am I missing?
 
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rlc said:
With the efficiency, I found:
1-(273/373)=0.268
And the heat of fusion for water is 3.34E5 J/kg
Given the efficiency and the quantity of heat input, how much work is output? How much heat is left to go into the cold reservoir?
 
You know T1 and T2 and Q1. Using zero universe entropy change as your criterion you can figure out Q2 and then of course the amount of ice meltred. Assume there is still ice left at T2 when the process ends (T2 is constant = 273K).
 
Would the work output be the efficiency times the J heat put into the engine?
 
Aha! I figured it out!
100-26.8% = 73.2%--of the added energy should be delivered as heat to the cold reservoir.
deltaH=m(Lf)
(0.732)(6437J)=m(3.34E5J/kg)
m=0.0141 kg ice melted

Thank you both for helping me!
 
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