Physics: Temperature Conversions and Heat Calculations



Honors Chemistry Name_______________________

Heat Calculations

*Use the table of specific heats from your notes to solve the following problems. Show all work, round answers to the correct number of significant digits, and label answers with the correct unit. Make sure the units for mass and specific heat match. Both must be either in grams or both in kilograms.

1. Calculate the amount of heat required to raise the temperature of 78.2 g of water from 10.0oC to 35.0oC. The specific heat of water is 4.18 J/goC .

2. Calculate the amount of heat required to raise the temperature of 22.1 g of aluminum from 27.0oC to 65.5oC.

3. How much heat must be removed from 15.5 g of water at 90.0oC to cool it to 43.2oC?

4. A 90.0 g sample of an unknown metal absorbed 25.6 J of heat as its temperature increased

1.18oC. What is the specific heat of the metal?

5. The temperature of a sample of water increases from 20.0oC to 46.6oC as it absorbs 5650 J of heat. What is the mass of the sample?

6. A 400.0 g glass coffee cup is at room temperature, 20.0oC. It is then plunged into hot dishwater, 80.0oC. If the temperature of the cup reaches that of the dishwater, how much heat does the cup absorb? Assume the mass of the dishwater is large enough so its temperature doesn’t change.

7. A 100 g mass of tungsten at 100.0oC is placed in 200 g of water at 20.0oC. The mixture reaches equilibrium at 21.6oC. Calculate the specific heat of tungsten.

8. A 600 g sample of water at 90.0oC is mixed with 400 g of water at 22.0oC. Assume no heat loss to the surroundings. What is the final temperature of the mixture?

9. If 335 g of water at 65.5oC loses 9750 J of heat, what is the final temperature of the water?

10. A breakfast of cereal, orange juice, and milk might contain 230 dietary Calories. Express this energy in joules.

11. Suppose that you consumed six glasses (250 g each) of ice water (0oC) on a hot summer day. If your body temperature is 98.6oF, how many calories of thermal energy did your body supply to heat this water to body temperature? How many Calories is this? How many joules?

12. How many glasses of ice water would you have to drink to “burn off” the 220 Cal of energy you would gain by eating a serving of french fries? Is drinking water an efficient way to diet?

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download