371 Lab Rybolt Data Analysis Assignment Name

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1 Data Analysis Assignment Lab Rybolt Data Analysis Assignment Name You wake up one morning and feel you may have a fever. You have an oral thermometer marked in Celsius degrees and find your temperature to be 40.0 o C. You cannot remember the normal body temperature in Celsius, but you do recall that in Fahrenheit it is 98.6 o F. You have an outdoor thermometer attached to the wall of your house. You think back to your college days at UTC and recall the best course you ever had physical chemistry! You have an idea and begin. Leaning out the window of your house, you place the oral thermometer next to the outdoor thermometer and record the temperatures on both as the outside temperature warms with the rising sun. You record the following data: Temp( o C) Temp( o F) ) Using good quality graph paper, hand draw the above data plotting o F versus o C. That is to say Temp( o F) along y axis and Temp( o C) along x axis. Note when defining a plot of data the y axis property is always given first as in the statement, plot Q vesus t. Since we always refer to y versus x then you know that Q is the along the y-axis and t is along the x-axis. Learning this simple rule will save you a trouble with incorrect plots. However, remember if using Excel, the columns are placed as (x,y) points so you would have columns of data in the order t then Q. Be sure to include title, label axes, indicate units, draw a circle around each data point and indicate the increments along the y and x axes. After you have placed points on page, use a ruler (judging by eye) and draw the best line through the data points. Staple the graph to these pages. 2) Pick out two points that are on the line and calculate the slope of the line, m, and the intercept, b. Recall that y=b if x=0 from the formula y=mx+b where m=(y 2 -y 1 )/(x 2 -x 1 ). Report results below. slope= intercept= 3) Use the original temperature data to calculate (show formulas and all steps of work) an exact value for slope, intercept and correlation coefficient based on the exact formulas for linear regression analysis. slope= intercept = r=

2 Data Analysis Assignment 2 4) Using Excel software enter the above data in a spreadsheet. Use the Excel software to plot a graph of data. Before printing make sure the background of the graph is white and not gray. Click on the background and you should get a color options. Adjust the y and x scales as necessary for good spacing, label axes, include correlation equation and r 2 value, make sure data points can be seen easily, and include a graph title. Go though these items each time you create a graph. 5) Using Excel apply linear regression to above plot and determine the following: slope= intercept= r = where r is the correlation coefficient. The correlation coefficient is a measure of fit where r=1 is a perfect line and r= 0 is completely random scatter). Note if your results in item 3 are not very close to 4 then most likely made a mistake in item 3. Recheck your work. Print your graph and staple to the back of these pages. 6) According to your linear regression obtained from the computer fit of data for the slope and intercept in part 5, what is your temperature formula o F = ( o C ) + and what is your temperature in Fahrenheit if it is 40.0 o C? 7) What is the correct value in o F based on accepted formula o F = 1.8 ( o C ) + 32 if your temperature is 40.0 o C? Report the following answers with units and to the correct number of significant figures and clearly show all your work including unit analysis. 8) Data is collected to 3 sig fig then used to make a plot whose slope has 2 sig fig and then the slope is used to calculated an experimental value that is reported to 5 sig fig. To be done correctly, the slope should have sig fig and the final answer should then have sig fig.

3 Data Analysis Assignment 3 9) The miles per gallon of a car that goes mi on 20.4 gal of gasoline. 10) The miles per gallon of a hybrid car that goes mi on gal of gasoline. 11) The total miles traveled on a three day trip if a car goes mi on day one, mi on day two and mi on day three. 12) There are 2.2 pounds of sodium chloride salt per cubic foot (lb/ft 3 ) of ocean water (recall that 1 lb = 454 g and 2.54cm = 1 in). Therefore how many grams of salt are there per liter of ocean water (g /L)?

4 Data Analysis Assignment 4 13) Given that water has a density of g/ml at a certain temperature, what is the molarity of pure water if expressed in terms of moles of H 2 O molecule per liter of solution? 14) How many molecules (number of molecules not moles) of water are found in ml of a 1.203M solution of glucose if the density of the solution is g/ml? 15) If a farmer and half (1.50) shoots a fox and half in a day and half while at the same time a fox and half eats a chicken and half in a day and half and at the same time a chicken and half lays an egg and a half in a day and a half, then how many eggs have been laid after 4.5 days if you start with 3 farmers, 9 foxes, 18 chickens and 0 eggs. For simplicity you can consider that these events occur at the very end of the 1.5 day time period so you can consider that the chickens lay eggs, then are eaten by foxes, and then foxes are killed by farmers. This discrete approach is simpler than having to deal with continuous processes. (show your work)

5 Data Analysis Assignment Graph paper insert 5