Minnesota State University, Moorhead *

*We aren’t endorsed by this school






Jan 9, 2024





Uploaded by MasterMousePerson897 on

Understanding Error Name: Hand-In, Chem 150L Partner: Measuring Density 1. (4 points) (a) Show a sample calculation of the density for one of your trials. (b) Calculate the average density of your unknown liquid, and (c) calculate the absolute error in the density. (d) Report your final result as the avg. density ± absolute error, rounded appropriately and including units. Show all of your calculations using the Equation Editor function in Microsoft Word. {Show calculations and type the properly formatted final result here. You can delete this text.} 2. (1.5 points) What is the percent error in the density of your unknown liquid? Again, show your work using Equation Editor and report your final result as avg. density ± % error. {Type calculation and answer here.} 3. (2.5 points) (a) List the number of your unknown liquid and what you determined its identity to be. (b) Based on your absolute error, is your average density value in agreement with the known value? (c) Show your percent difference calculation. {Type answers and calculation here.} Determining “Room Temperature” 4. (2.5 points) (a) Calculate the average room temperature for the lab, and (b) calculate the absolute error in the temperature. Show your work. (c) Report your final result as avg. temp. ± absolute error, including units. (d) Additionally, explain in words why you rounded your absolute error and average temperature values as you did. {Type calculations and answer here.} 5. (1.5 points) What is the percent error in the average room temperature? Express your result as avg. temp. ± % error. Show your work. {Type calculation and answer here.} 6. (1 point) What are some potential sources of error/variability in your temperature measurements, i.e., what might be causing the differences in the measured temperatures? List and explain as many as you can. Note that “human error” is a mistake, not a legitimate source of error. Do not list “human error.” {Type answer here.} 7. (2 points) Compare your average lab temperature to that of another group. Are the results different enough (considering the absolute errors/uncertainties) that you can consider your result different from the other group’s result? Is it possible that you are both reporting acceptable values, even though you may be
reporting different values for the average? Be sure to report the values you are comparing and to explain your answer, using the errors in both measurements to support your argument. Your value: _____ ± _____°C Other group’s value: _____ ± _____°C {Type answer here.} See the rubric below for more detailed information about grading. Unsatisfactory Borderline Satisfactory Excellent Score Q #1 Density, avg ±error No work shown . 0 points Multiple calculation and rounding errors. 1 point Incorrect precision on reported error and average. -0.5 pt for each minor mistake. 3 points Density correct, 1 pt. Average correct, 1 pt. Error correct, 1 pt. Error rounded to one digit and average reported to precision of error, 1 pt. 4 points 4 pts. Q #2 Density, % error No work shown. 0 points Incorrect calculation. 0.5 point Incorrect rounding or no reporting of avg ± % error. 1 point % error calculated and rounded properly. Avg. ± % error reported. 1.5 points 1.5 pts. Q #3 Density, compari son All parts incorrect. 0 points Multiple mistakes. 1 point -0.5 pt for each minor mistake. 2 points Correct identity, 0.5 pt. Valid comparison, 1 pt. % difference, 1 pt. 2.5 points 2.5 pts. Q #4 Temp Sig fig Disc. No calculations shown and no explanation of precision. 0 points No explanation of rounding. 1.5 points No units, incorrect rounding of either average or error, or minor mistakes. 2 points Correct calculations (1.5 pt) and discussion (1 pt) of rounding based on the precision of the error. 2.5 points 2.5 pts. Q #5 Temp % error No calculations shown. 0 points Error in calculation. 0.5 point Incorrect rounding or average ± % error not reported. 1 points Percent error properly calculated and rounded. 1.5 points 1.5 pt. Q #6 Temp cause of error Sources of error not identified or not reasonable. 0 points One reasonable source of error identified. 0.5 point 2-3 reasonable sources of error identified. 1 point 1 pts. Q #7 Temp com- paring No or unreasonable comparison made. 0 points Comparison made incorrectly. 1 point Correct comparison, but poor explanation. 1.5 points Correct comparison of answers based on your and other’s errors. 2 points 2 pts. Total 15 pts
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help