1. The problem statement, all variables and given/known data If you pour 0.50 kg of molten lead at 328°C into 2.5 liters of water at 20°C, what will be the final temperatures of the water and the lead? The specific heat of (solid) lead has an average value of 3.4 X 10-2 kcal/kg • °C over the relevant temperature range. 2. Relevant equations Q=mass*c* [tex]\Delta[/tex] T Qfus=m*cfus masspb=0.50 Kg @328oC cpb=34 cal/KgoC Tfinal=? cfusion=6800 cal 3. The attempt at a solution Qfusion=6800 cal/Kg * 0.50 Kg= 3400 cal Qpb = 3400 cal + .50Kg * 34 cal/KgoC* (328-x) Qpb=3400+5576-17x For Water: QH2O=2.5 Kg * 1000 cal/KgoC * (x-20oC) QH2O=2500x-50000 Setting these equal to each other I get: 2500x-50000=3400-17x+5576 2517x=58976 cal x=23.4311oC The back of the book has the answer of 22oC. I can get 22oC as an answer only if I subtract the latent heat of fusion: 2500x-50000=17x+5576 2517x=55576 x=22.0803oC The math seems pretty straight forward, so it makes me wonder whether the book made an error, or I did. Any help would be appreciated! Thanks.