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Experiment No. Determining the Specific Heat of an Unknown Metal 5 INTRODUCTION We have discussed several topics in thermochemistry. One of the main equations we use to calculate heat transfers was q=msΔT. For this topic you need to find a method that will allow you to calculate s, or the specific heat, of an unknown metal that I will provide you. You will need to get your procedure approved by me before beginning your experiment. You will be allowed to use all of the same equipment as used in the first laboratory activity that we did for this topic. After completeing this laboratory experiment, you will be producing a laboratory report. Be sure to follow the rubric provided. You will be required to include an introduction, an experimental procedure, a results section, and a discussion section. The introduction should include the theory behind the topic being done. The experimental procedure should include all the steps you preformed to complete the experiment. The results section should summarize the results of the lab in a table or graph whichever is more convenient. You should make sure to include all the data you collected. The discussion section is where you should report any values you calculated from the data you collected. You should also discuss what metal you think you were given by doing some research. Be sure to cite any sources you used at the end of your paper. DETERMINING THE IDEAL GAS LAWDETERMINING THE IDEAL GAS LAW 27 Data and Calculations DETERMINING THE IDEAL GAS LAW 28 DETERMINING THE IDEAL GAS LAW 29 Pre-Lab Questions 1. Manipulate the ideal gas equation (PV=nRT) to find the pressure of the gas as a function of volume. (Hint: get pressure on side of the equation and volume on the other side.) What is your independent variable ( what are you changing throughout the experiment) and what is the dependent variable (what are you measuring on the computer). What should the slope be equal to if you think about it in the form y=mx+b (x is your independent variable and b is the y intercept and can be zero.) 2. This experiment assumes that the temperature remains constant and the temperature of the gas is the temperature of the room. Is this a reasonable assumption? Why or why not? 3. A student did this lab and determined that the slope of the line for the data was 0.0114. The volume the gas took up in the syringe was 10.8 mL. The temperature of the room was 21°C. Determine the value for R, the gas proportionality constant, for this data. Make sure to find all variables and get them to the correct units. Assume ideal gas behavior. DETERMINING THE IDEAL GAS LAW 30 Post-Lab Questions 1. Provide a graph for the data showing the relationship between volume and temperature and the pressure and volume. Extrapolate the temperature needed for the volume to be zero based on a best-fit line. 2. Why did you graph the relationship between pressure and 1/volume not pressure and volume. (Think about the question in the pre-lab) 3. Determine the percent error for all of your R-values. 4. Why would there be a difference between your R-value and the R-value for an ideal gas? DETERMINING THE IDEAL GAS LAW 31