Fundamentals Results Summary
Grades: PreLab (5)
Summary (20)
Notebook (5)
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Name_______________________________
Section # __________
Date Expt Completed ________
Date Report Submitted _______________
PreLab Notebook Page #’s ____________ Lab Notebook Page#’s__________
Reporting Your Results for Penny Statistics (10)
**Only include spreadsheet data for the actual calculations and a sample
calculation. (Do not submit the raw data.)
Attach a table of masses, with one column sorted by mass for each year.
Divide 1982 into two columns, one for light (zinc) and one for heavy (brass) pennies.
One year should be divided into one column from Denver and one from Philadelphia.
Discrepant Data
1. List the mean ( x ) and standard deviation (s) for each column.
2. Discard data that lie outside of x ± 4 and re-compute x and s. You must identify the
outlier and justify why it was discarded.
Confidence Intervals and t-Test: Include a sample calculation!
1. For the year ≥1982 with highest average mass:
95% confidence interval =
= _____________________
For the year ≥1982 with lowest average mass: 95% confidence interval =
Comparison of means with t-test:
t calculated (equation 8) = ________________________
t table (Table 1) = ______________________
Is the difference significant and why?
2. For the year ≤1982 with highest average mass: 95% confidence interval =
For the year ≤1982 with lowest average mass: 95% confidence interval =
Comparison of means with t-test:
t calculated (equation 8) = ____________________
t table (Table 1) = ___________________
Is the difference significant?
3. For Philadelphia versus Denver coins in one year:
Philadelphia 95% confidence interval = _____________________
Denver 95% confidence interval = ________________
Comparison of means with t-test:
t calculated (equation 8) = __________________
t table (Table 1) =
___________________________
Is the difference significant?
Calibration of a Volumetric Glassware (10)
1. Buret Calibration. Use Table 3 to convert the mass of water to the volume delivered at
the specific temperature. Determine your corrections. Repeat any set of duplicate buret
corrections that do not agree to within 0.04 mL. Prepare a scatter plot like that in Figure
4, showing the correction factor at each 5-mL interval. (Attach the plot.)
2. For all volumetric glassware, calculate a mean and standard deviation for each set of
measurements. (Report all results as volumes of water dispensed, in milliliters.
Remember to use Table 2-7 (third column) when calculating volumes of water from
your masses.)
3. Calculate the relative uncertainty and percent relative uncertainty for the
measurements made with the volumetric pipet, Mohr pipet and the Buret. (Note that
the absolute uncertainty is the standard deviation you calculated in part 1 for each
set of measurements.)
4. Comment on your results: Which transfer device was the most accurate? With which
device did you obtain the most precise results? Where is error introduced into this
experiment? (Consider both systematic and random error; also consider how the
relationship between the volume you delivered from the pipet/buret and the total
volume that the pipet/buret can hold will affect your results.)