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**Thermodynamics...I have been working on this for 3 hours :(**

Please help anyone :), I have been trying this problem for the past 3 hours and I am not getting the right answer. I would appreciate any hint or guideance.

Thanks all

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" A copper calorimeter can with a mass of 0.100 kg contains 0.160 kg of water and 0.018 kg of ice in thermal equilibrium at atmospheric pressure. If 0.755 kg of lead at a temperature of 280°C is dropped into the calorimeter can, what is the final temperature? Assume that no heat is lost to the surroundings."

Mass of copper= .1kg

Mass of water=.16kg

Mass of ice= .018kg

Mass of lead= .755kg @ 280ºC

I assume that since the ice is in thermal equilibrium with the copper cup and water then the temperature is 0ºC.

The target variable is the common final temperature(T).

Using 17.13(Q = mc∆T) I set up all of the above elements including the heat transfer of the phase change of ice(Q=mL).

(.018kg)ּ(2100J/kgּK)ּ(T-0ºC)+(.1kg)ּ(390J/kgּK)(T-0ºC)+(.16kg)ּ(4190J/kgּK)ּ(T-0ºC)+(.018kg)ּ(334000J/kg)+(.755kg)ּ(130J/kg)ּ(T-280ºC)=0

Solving for final temperature, I get close to 25.3977ºC which doesn't seem to be the correct answer.

Please help with a hint,

Thanks