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Graphing with Excel Assignment.This is not a formal lab report, however you will submit your work through Canvas. Questions and calculations may be handwritten or typed, then scanned and uploaded to the assignment. Please embed the graphs and spreadsheet in the document. In this lab you will use Excel, Google Sheets or another graphing program to plot data. Note Office 365 available free to students on Canvas will not allow you to add trendlines and you will have to use Sheets instead if you don’t have regular MS Office.No matter what program you are using,Note that in the spreadsheet, the x-axis data needs to be on the left of the y-axis data column.Always use a scatter plot with no initial lines (you will add trendlines when needed)The graph automatically generated by graphing programs is never correctly formatted for submission in a science course. Below are features of a good graph. Be sure any graph you turn in for this class adheres to these guidelines. Each graphing program has different ways to change graph formatting. Use a search engine to find out how to do it in your program/Mac/PC/version.Give the graph a descriptive title. Don’t just repeat the information in the axes titles. Pressure vs Temperature…for what? Look in the instructions above to find what substance this data is for. Your title should describe what the experiment was about.Label axes with the type of unit and the unit itself. For example: Temperature (oC). Axes should be at the bottom and left of the graph – not in the middle of the data. Remove the legend if it provides no information. Most Excel versions default to having legends for every graph. If you are only plotting one set of data per graph, the legend contributes nothing – get rid of it.Change the start and end points of each axis so that the data takes up the majority of the graph. Excel usually defaults to having both axes start at zero. This often leads to the graph having a lot of white space, which we do not want. Change the minimum value of each axis so that it starts just below your lowest data point.Add a trendline when appropriate. If you want to find a mathematical relationship in the data, be sure to include a trendline and to check the box to display the equation on the chart. You can also choose to display the R2 value. The closer the value of R2 is to 1, the better the fit. You will add trendlines to all three graphs in the exercise.Add more gridlines when appropriate. In this exercise we are only concerned with the trendline, but in some labs you will need to estimate a value off the graph after printing. If this is the case, be sure to add enough gridlines so that you can accurately estimate your value. If you need to read a value to the nearest 0.1 mL, but your x-axis only has gridlines every 5 mL, your estimate will be poor.Print or embed your graphs at a reasonable size. Usually about ? page is appropriate. Also print/include the spreadsheet when asked. Name_________________________CHM112 Lab – Graphing with Excel – Grading Rubric CriteriaPoints possiblePoints earnedGraphs correctly plotted and adhere to all guidelines (including descriptive title, properly formatted axes, trendline equations displayed)Graph A4Graph B4Question 1 1Question 2 1Question 31Question 41Question 5 1Question 6 (work shown clear in detail in with units)2Question 7 (work shown clear in detail in with units)2Question 8 (work shown clear in detail in with units)2Total20 Subject to additional penalties at the discretion of the instructor.Temp (°C)VP chloroform (Torr)VP Ethanol (torr)5.087.517.310.0106.923.620.0159.843.930.0238.878.840.0357135.350.0533.4222.260.0797.3352.7Part A: Graph all the above data on the same plot. Construct a scatter plot of the vapor pressure of chloroform and ethyl alcohol as a function of temperature. Temperature on the x axis and VP on the y axis.Add a best fit line or trendline for each. (select the best possible trend or regression type)Display the best fit equation (trendline equation) for each data set on the chart and also display the R2 value.Turn in the graph (Graph A), the spreadsheet as well as a typed or hand-written discussion of the following questions! All graphs and questions must be done individually. If 2 students turn in identical graphs or answers, both will receive a zero. According to graph A, what is relationship between vapor pressure of a liquid and temperature? Does this relationship match what you learned in lecture?Look up or draw the Lewis structure of chloroform (CHCl3) and ethanol (CH3CH2OH). List all IMFs present in each compound. Which has stronger attractions?Read the graph and write the vapor pressure of each substance at 40°C. Which is higher? Which would you expect to be higher based on IMFs? If the external pressure were dropped to 280 mm Hg, which substance(s) would boil or be boiling at 55°C ? Explain how you know. Use the graph to answer this question.Part B You can handwrite your calculations and scan them and upload to Canvas.Plot both sets of data from part A using the linear form of the Clausius Clapeyron (Graph B) with (1/T) in Kelvins on the x axis and ln(Vapor Pressure) on the y axis. Use Scatter plots!)Add a best fit line or trendline for each. Please note that the trendline is actually a “best fit line” that takes into account all the data points. We will always use this line for calculations. Make sure to select the best possible fit for the trend or regression type. Display the equation for each on the chart.Display R-squared value on the chart for both liquids.Submit graphs and spreadsheet through Canvas. All graphs must be done individually. If 2 students turn in identical graphs, both will receive a zero.This is the linear form (y = mx + b) of the Clausius-Clapeyron: ln(VP)= -?HVapR 1T +C : where R = 8.314JK molAnswer the following based on Graph B. REMEMBER you just did calculations like this in the Math Review!!In the linear form of the Clausius-Clapeyron (see above)What does the y correspond to? What does x correspond to? What does the slope (m) correspond to?Using the just the slope value from your best fit line (or trendline) for the linear plots, calculate ?Hvap for both liquids.Using your best fit line (or trendline), calculate the Normal Boiling Point for each liquid. Using the best fit line (or trendline), calculate the Vapor Pressure of each liquid at 75 °C. ................
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