Help with Data Analysis for the Osmosis Lab
Here is what you should have on your graph:
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A best fit line
An equation for the line in y=-mx+b form
An R2 value that is between 0 and 1
Here is what you should write in your trend based on this information (trend for this lab will be at
LEAST three sentences):
1. What does your best fit line say: Think—“As…..increases…….”
2. R-squared—tells you how good the best fit line is. An R2 of 0 is a terrible line. An R2 of 1 is
a perfect line (which you will never actually get when doing science)!. Based on the R2 you
calculated explain if you should use your line to draw conclusions.
3. y=-mx + b. Look at the equation of the line.
a. What variables are given? (answer m and b).
b. What is x (answer concentration)
c. What is y (answer % change)?
*If % change in mass is zero, what will the sugar concentration be? Use the equation for
the line to figure this out (hint you must substitute zero for either X or Y. Think about what
you want to solve.
*Once you find the concentration of sugar, explain what that means.