You are going to study what happens to the temperature of water when different metals are added to it. Before doing the activity, think about the following questions.

1. Suppose that equal masses of water and iron are at the same temperature. Suppose you then add the same amount of heat to each of them. Would one change temperature more than the other?
(circle one)             Yes         No

If you circled "Yes," which one would warm more?
                            Water          Iron

2. Again suppose that equal masses of water, iron and wood are at the same temperature. You then add the same amount of heat to each. Would one change temperature more than the other?
                            Yes             No

If you circled "Yes," which one would warm more?
                            Wate             Iron                Wood

PROCEDURE:

Make data sheet
Step 1: Read over the entire lab sheet and make a data sheet to record all the measurements that you will be asked to make. Every place the instructions say to record something that is a clue to what to add to your data sheet.

Mass cup and water
Step 2: Get one styrofoam cup. Place it on a triple beam balance. Measure and record its mass.

Step 3: Fill the cup to the mark with cold water. Measure and record the mass of the cup + water.

Step 4: Calculate the mass of just the water and record it.

Mass metal sample
Step 5: Get a metal sample from your instructor. Record the type of metal. If it is not marked on the sample ask your instructor. Measure the mass of the sample and record.

Heat the metal sample
Step 6: Attach a metal wire to the sample and place the sample in boiling water. Leave there for 15 minutes.

Measure temperature of sample ÷ The sample has been sitting in boiling water for 15 minutes. It will be at the same temperature as the water.
Step 7: Measure and record the temperature of the boiling water. Record this as the temperature of the mass.

Predict temperature of mixture
Step 8: Using the mass of the cold water, the temperature of the cold water, the mass of the sample and the temperature of the sample predict what the temperature of the mixture will be when the hot sample is added to the cold water. Record this as "Predicted Final Temperature of First Mixture."

Measure temperature of mixture
Step 9: Place the sample in the cold water. Place your thermometer in the cold water. Do not touch the sample with the thermometer. Measure and record the highest temperature the water reaches. This should take be when the thermometer no longer rises after a 15 seconds.

Question 1. How close was your prediction to the observed value? Find the percent relative error by using the method shown by your instructor.

Second sample
Step 10: Obtain a second sample from your instructor. Repeat steps 1 through 9 with the second sample. At step 8, try and use what you learned from the first trial to make a more accurate prediction.

Question 2. How close was your prediction to the observed value? Find the percent relative error by using the method shown by your instructor.

 
ANALYSIS:
Answer questions 1 & 2.

Finding Heat Capacity ÷ Do this first for the first sample and then do it again for the second sample
1. Calculate the change in temperature of the water after you added the hot metal. Call this change DTH2O.

2. Calculate the change in the temperature of the hot metal after you added it to the water. Drop and minus sign. Call this change DTmetal.

3. Call the mass of the water you found in step 4 MH2O. Call the mass of the sample your found in step 5 Mmetal.

4. The heat capacity of any object is called Cs. Cs for water is 4.184 J/g·DC. Use the equation below to find the heat capacity of your sample. Call that Cs metal.

C_s = (4.184 J/gC) x (M_H20) x (DT_H20)
                    (M_metal) x (DT_metal)

5. Find the percent relative error for each sample.

CONCLUSION:
Report your values for the specific heat of each sample along with the percent relative error.