1. The problem statement, all variables and given/known data If 100 grams of glass (specific heat .2 cal/g*°C) at a temperature of 500 °C is added to 20 g of 0°C water, what is the final equilibrium temperature? 2. Relevant equations Q= mcΔT 3. The attempt at a solution I know that I have to set the two equation against each other: (100 g)*(.2 cal/g*°C)*(500°C -T) = (20 g)*(0°C+T) 20*(500-T)= 20T 10,000 - 20T= 20T 10,000 = 40T 250 = T I have an answer of 250°C, but my answer key says that the correct answer is 100°C. Any help?? Thank you!