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fabbo
Nov30-05, 11:43 AM
Ok, I had these questions for homework and had no problems with them except this one.

A variety of carrots has a specific heat capacity of 3700J/Kg/K. A saucepan of boiling water is used to raise the temperature of 825g of these carrots to 100 C. The carrots are then drained and immediately transferred to a large amount of ice and water in a plastic bowl. some of the ice still remains when the carrots achieve thermal equilibrium with the ice/water mixture. The specific latent heat of fusion of water is 330kJ/Kg. Calculate the mass of ice that melts during this process.


The only way I know how to work it out is by first calculating the energy put into the carrots using the specific heat capacity equation but we are not given a temperature rise. Should I assume the rise is 100 C. Any help is gratefully received. X

Doc Al
Nov30-05, 11:48 AM
You are told that the carrots--just before they are transferred to the bowl of ice/water--were at a temperature of 100 C. That's the initial temperature of the carrots. Since some ice remains after equilibrium is reached, what must be the final temperature of the carrots?

fabbo
Dec1-05, 11:10 AM
You are told that the carrots--just before they are transferred to the bowl of ice/water--were at a temperature of 100 C. That's the initial temperature of the carrots. Since some ice remains after equilibrium is reached, what must be the final temperature of the carrots?

oh i get it now - thank you!