The teacher doesn't go slow enough, and make sure you understand the material.. What he goes over in class isn't on the test or homework, so im close to failing. I was hoping to get some help. I have an online test tomorrow (friday) and was hoping i could post some questions, and maybe get some help on them.. Here is one of the questions that might be on it. How many calories of heat are required to convert .250 kg of ice at 0 °C into steam at 100 °C? Solve this problem in steps: How much heat is required to melt the ice and produce water at 0 °C? How much heat is required to raise the temperature of the water to 100 °C? How much heat is required to boil the 100 °C water into water vapor (steam) at 100 °C? What is the total amount of heat that was added to the original ice at 0°C to turn it into steam at 100 °C? And the answers must be in Kcal... Thats a question on the homework.. and i dont even understand that.. any body lend some help?