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apbuiii
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Homework Statement
Suppose you put a coffee pot containing 300 g of water at 20 C on the stove. You then add 350 kJ of heat to the water, which heats the water to 100 C and the water starts to boil. After all the heat is added to the water, then how much water do you still have left? The heat of fusion for water is 6.01 kJ/mol and the heat of vaporization is 40.7 kJ/mol.
Homework Equations
q=mass(specific heat)(Tf-Ti); q=moles(delta-enthalpy)
The Attempt at a Solution
I first found how much energy it would take to evaporate all of the 300 grams. (100-20)(300g)(4.18) + (40.7 KJ)(300)(1mol/18g)(1000J)= 778653 J. So I then set up a ratio that if 778653 evaporates 300 grams then how many grams will 350000 J evaporate. 778653/300 = 350000/X. That gave me 135 grams evaporated. So I then minused that from the 300 giving me 165 grams left. Seemed reasonable to me but I got it wrong! Please help, but showing the steps to find the answer would be even more helpful! Thanks