Practice Problems
Specific Heat Chart
Substance                                  Specific Heat (cal/g�C)
       Air                                                                0.25
  Aluminum                                                          0.22
    Copper                                                            0.09
     Glass                                                              0.20
      Iron                                                               0.11
   Wood                                                               0.42
   Mercury                                                           0.03
Fresh Water                                                       1.00
Ocean Water                                                      0.93
Sample Problems
1. How much heat is needed to raise the temperature of 5 grams of copper by 10�
Celsius?

First we identify the information we are given in the problem: 
    mass = 5 g 
    change in temperature = 10�C 
    specific heat of copper = 0.09 

Next, we place this information into the formula:
        heat gained = mass x change in temperature x specific heat 
        heat gained = 5 g x 10�C x 0.09 cal/g�C 

Solving the equation gives a heat value of 4.5 cal
A 50 g substance loses 23 calories of heat energy when the temperature falls from 35�C to 20�C.  What is the specific heat of the substance?

We identify the information given in the problem: 
    mass = 50 g 
    heat lost = 23 cal 
    change in temperature = 15�C 

We now place the information into the formula: 
     heat gained = mass x change in temperature x specific heat 
     23 cal = 50 g x 15�C x specific heat 
     23 cal/50 g x 15�C = 50 g x 15�C x specific heat/50 g x 15�C 

Solving the equation gives a specific heat value of 0.03 cal/g�C
2.
A piece of food is tested in a calorimeter to ascertain how much heat energy it contains.  If the water in the calorimeter has a mass of 150 g and the temperature of the water increases by 3�C, how much heat energy was released by the burning of the food?

Identify the information given to you in the problem: 
    mass = 150 g 
    change in temperature = 3�C 
    specific heat of water = 1 cal/g�C 

Insert the information into the formula:
    heat gained = mass x change in temperature x specific heat 
    heat gained = 150 g x 3�C x 1 cal/g�C 

Solving the problem gives a heat energy value of 450 cal for the food.
3.
Practice Problems
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