1. Chapter 11 Notes II Calorimetry

2. What is calorimetry? Essentially, the science of measuring heat change. At its most simple, you use the specific heat of something you know to find the specific heat of something you don’t.

3. It takes advantage of the law of conservation of energy. What is calorimetry? The principal shows that heat lost by one substance has to equal heat gained by another.

4. When a hot object is put into cool water what happens? Object at 100 o C Water at 20 o C Final temperature of both is 22 o C 50g 250g 50g

5. Heat lost is equal to heat gained, but temperature lost does NOT equal temperature gained NOTICE:

6. So, to find the specific heat of the object… Solve q=mCT for heat gained by water THEN Use q you found to solve q=mCT for the specific heat of the object.

7. Calorimeters A calorimeter is a device that measures heat change. It can be extremely sophisticated, or as simple as two foam cups, a thermometer and water!

8. Constant Pressure Style Calorimeter

9. Bomb Calorimeter

10. Practice Problem #1 What is the specific heat of a metal if a 50.8g sample at 100.0 o C raises the temperature of 258.2g of water from 25.2 o C to 28.1 o C?

11. What is the specific heat of a substance if a 22.6g sample at 104.5 o C raises the temperature of 125.3g of water from 22.6 o C to 33.1 o C? Practice Problem #2