Specific Heat of Metal

Lab # 16

Heat Transfer

Specific Heat of Metal

Purpose: To determine the specific heat of a metal. (STD 4d)

Background

On a sunny day, the water in a swimming pool may warm up a degree or two while the concrete around the pool may become too hot to walk on in your bare feet. This may seem strange because both the concrete and the water are being heated by the same source-- the sun. This evidence suggests it takes more heat to raise the temperature of some substances than others. This, in fact, is true: The amount of heat that is required to raise the temperature of 1 g of a substance by 1 oC is called the specific heat capacity, or simply the specific heat, of that substance. Water, for example, has a specific heat of 4.184J/goC = 1cal/goC The specific heat of water is also 1 cal/goC. This value is high in comparison with the specific heats for other materials, such as concrete. In this experiment, you will use a simple calorimeter and your knowledge of the specific heat of water to determine the specific heat of a metal.

Materials

Safety gogglesbalance

400 mL beakerfoam cup

hot platethermometer

tongsmetal block

50 mL graduated cylinder

Procedure

1. Heat 250 mL of water in a 400 mL beaker until it is boiling
2. While the water is heating find the mass of the block you are given and record in the data table.
3. Put exactly 100 mL of H2O in a Styrofoam cup. Record the mass of the water as 100 grams in the data table. (because for water 1ml = 1g)
4. Record the temperature of the water in the Styrofoam cup as the initial temperature in the data table.
5. Transfer the block into the boiling water and let it boil gently for 5 minutes.
6. Record the temperature of the boiling water in the data table.
7. Record the initial temperature of the metal as the temperature of the boiling water.
8. Quickly transfer the block into the Styrofoam cup and take the temperature of the water until the temperature stops rising. Record that temperature as the final temperature of the water and the metal in the data table.

Data Table: Measurements of Mass and Temperature

Analysis and Conclusions for Metal 1

1. What was the final temperature of the metal?

2. What was the initial temperature of the metal?

1. What was the T for metal (tf-ti)

1. What was the T for the water (tf-ti)

5. What was the mass of the water?

1. Calculate the heat change for the water Q = mCT

1. What was the heat change for the metal? (Hint: Where did the heat for the water come from?) Qmetal = -Qwater

1. Calculate the specific heat of the metal. Q = mCT

C = specific heat m = mass of metal T is for the metal

1. Calculate the percent error in the specific heat value that you determined experimentally. Use the accepted value given by your teacher.

% Error = accepted value – experimental value x 100

accepted value

Analysis and Conclusions for Metal 2

1. What was the final temperature of the metal?

2. What was the initial temperature of the metal?

3.What was the T for metal (tf-ti)

4.What was the T for the water (tf-ti)

5. What was the mass of the water?

6.Calculate the heat change for the water Q = mCT

7.What was the heat change for the metal? (Hint: Where did the heat for the water come from?) Qmetal = -Qwater

8.Calculate the specific heat of the metal. Q = mCT

C = specific heat m= mass of metal T is for the metal

9.Calculate the percent error in the specific heat value that you determined experimentally. Use the accepted value given by your teacher.

% Error = accepted value – experimental value x 100%

accepted value

Accepted Specific Heats

Al = 0.899 J

g oC

Cu = 0.385 J

g oC

Pb = 0.129 J

g oC

Sn = 0.222 J

g oC

Zn = 0.385 J

g oC