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**1. Homework Statement**

Calculate the quantity of heat absorbed (+) or released (-) during each of these changes: A. 250g. of water (about 1 cup)is heated from 15 degrees centigrade to 100 degrees; B. 500g. of water is cooled from 95 degrees centigrade to 55 degrees; C. 5.0ml. of water at 4 degrees centigrade is warmed to 44 degrees centigrade. Be sure to show all your calculation work in each case.

**2. Homework Equations**

My book gave me the formula 1.00 cal/g x C (with the degrees “dot,” – don’t know how to insert it in typing). It said that this means 1 cal will raise the temp of 1 gram of water by 1 degree. The book also gave another forumla to use 4.18J/g x C (again degrees)

**3. The Attempt at a Solution**

Which formula should I use for this question? I realized that an increase in temp = absobed heat and decrease in temp = released heat, so A and C would be absorbed heat and B released heat. Also, when the question uses centigrade, is it ok to think of it as Celsius? I read that they are pretty interchangable, but I want to make sure it isn't a "trick" question.

A. 1.00 cal / 250g x C (temp.) Is the temp the 15, 100 or the difference between the two (85).

B. 1.00 cal / 500g x C (temp) Is the temp the 95, 55 or the difference of 40?

C. Since this one is in mL, I am a little uncertain if this formula still applies as it is in grams. Or do I need to do some converting?

I am under the impression that quantity of heat thing has some thing to do with Joules. So should my answer be in Joules?