Percent Composition Lab
Name:
____________________________
IS
DOUBLE STUFFED REALLY DOUBLE STUFFED?
A specific brand of cookie (beginning with the letter O made by Mr. C) claims
that their doublestuffed cookie contains twice the amount of filling as their
regular brand. But is this claim really true?
Background Information:
Percent composition of a compound tells you the percent (by mass) of each
element in the compound. We
determine percent composition by comparing the mass (grams) of each element in a
compound to the entire mass (grams) of the whole compound. Then we multiply by
100 to turn the number into a percent.
For example, suppose you sleep seven hours each night.
What percentage of each day do you spend sleeping?
(Hint: Divide the number of hours you spend sleeping by the total number
of hours in a day. Then multiply
the answer by 100 to get the percentage). Show your work below:
Purpose:
Calculate
and compare the
percent of cream filling, by mass,
of a regular versus a double stuffed
Oreo cookie. Treat the Oreo cookie as one compound and the two parts (the cookie
and the filling) as the two different elements.
Hypothesis:
Double stuffed cookies contain twice the amount of creamy goodness
Materials:
a scale, a metal scoopula, 1 regular cookie, 1 double stuffed cookie, paper
towel
Procedures:
Data Table:
Type of cookie 
Mass of cookie (g) 
Mass of dough (g) 
Mass of cream filling (g) 
% composition of cream filling 
Regular Stuffed 




Double Stuffed 




Conclusion: Is the hypothesis correct or are double stuffed cookies a ripoff? Explain your answer.
Questions: