Data & Analysis Sheet Name: Matthew Woods Part 1: Vinegar reacting with calcium carbonate in eggshells 1. Describe what you saw each time you stirred the mixtures, including final observations of each. 2. In words only, write the chemical reaction occurring when vinegar and the eggshell react. It’s similar to Equation #7 in the instructions (but just use words, not formulas). Here’s the beginning: “Calcium carbonate plus acetic acid react to yield….” CaCO3+ 2H+ -> Ca+2 + H2O +CO2 3. What gas is in the bubbles produced? 4. In Cup 1, what is the limiting reactant and what evidence do you have to support your claim? 5. In Cup 2, what is the limiting reactant and what evidence do you have to support your claim? Part 2: Experimental Data for Baking Soda and vinegar reacting Data Mass baking soda (alone) Mass of beaker (alone) Vinegar % Mass vinegar + beaker Mass vinegar (alone) Mass mixture + beaker after reaction Mass mixture (only) after reaction Part 2: Table for Calculation Results (Show work below this table and enter final results here) Results 6. Molar mass of sodium bicarbonate 7. Moles of sodium bicarbonate 8. Mass of acetic acid in vinegar 9. Molar mass of acetic acid 10. Moles of acetic acid 11. Total initial mass of reactants 12. Final mass of mixture 13. Difference in mass = initial mass – final mass = carbon dioxide produced (actual yield) 14. Limiting Reactant 15. Theoretical yield carbon dioxide 16. % yield carbon dioxide Be careful of sig fig in your measurements and calculations. Calculations (Show all work by each question below and then enter the final results of each calculation into the table above.) Please make your answers stand out by bolding or coloring them. 6. Determine the molar mass of sodium bicarbonate. 7. Calculate the number of moles of sodium bicarbonate using the mass of baking soda. 8. Determine the mass of acetic acid used in the experiment. You need to look on your bottle of vinegar to do this. If your vinegar is 4 %, this means that every 100 g of vinegar contains 4 g of acetic acid. (If it is 5 %, then 100 g contains 5 g of acetic acid). To calculate the mass of acetic acid, use the following equation. For 5 %, replace 0.04 with 0.050. Record results in table. You can assume the percent has 2 sig figs. mass of acetic acid = mass of vinegar x 0.040 9. Determine the molar mass of acetic acid, HC2H3O2. 10. Determine the number of moles of acetic acid in each sample of vinegar. Hint: you need to use the mass of acetic acid, not the mass of vinegar. 11. Add the mass of baking soda and vinegar initially. This is the total initial mass of reactants. 12. Record the final mass of mixture.
 13. Determine the total mass gain or loss for the reaction by comparing your initial mass to the final mass of mixture. This is the mass of carbon dioxide lost which is your actual loss. 14. Compare the .

1. Data & Analysis Sheet
Name: Matthew Woods
Part 1: Vinegar reacting with calcium carbonate in eggshells
1. Describe what you saw each time you stirred the mixtures,
including final observations of each.
2. In words only, write the chemical reaction occurring when
vinegar and the eggshell react. It’s similar to Equation #7 in the
instructions (but just use words, not formulas). Here’s the
beginning: “Calcium carbonate plus acetic acid react to
yield….”
CaCO3+ 2H+ -> Ca+2 + H2O +CO2
3. What gas is in the bubbles produced?
4. In Cup 1, what is the limiting reactant and what evidence do
you have to support your claim?
5. In Cup 2, what is the limiting reactant and what evidence do
you have to support your claim?
Part 2: Experimental Data for Baking Soda and vinegar reacting
Data
Mass baking soda (alone)
Mass of beaker (alone)
Vinegar %
Mass vinegar + beaker

2. Mass vinegar (alone)
Mass mixture + beaker after reaction
Mass mixture (only) after reaction
Part 2: Table for Calculation Results (Show work below this
table and enter final results here)
Results
6. Molar mass of sodium bicarbonate
7. Moles of sodium bicarbonate
8. Mass of acetic acid in vinegar
9. Molar mass of acetic acid
10. Moles of acetic acid
11. Total initial mass of reactants
12. Final mass of mixture
13. Difference in mass = initial mass – final mass = carbon
dioxide produced (actual yield)
14. Limiting Reactant
15. Theoretical yield carbon
dioxide
16. % yield carbon dioxide

3. Be careful of sig fig in your measurements and calculations.
Calculations (Show all work by each question below and then
enter the final results of each calculation into the table above.)
Please make your answers stand out by bolding or coloring
them.
6. Determine the molar mass of sodium bicarbonate.
7. Calculate the number of moles of sodium bicarbonate using
the mass of baking soda.
8. Determine the mass of acetic acid used in the experiment.
You need to look on your bottle of vinegar to do this. If your
vinegar is 4 %, this means that every 100 g of vinegar contains
4 g of acetic acid. (If it is 5 %, then 100 g contains 5 g of acetic
acid). To calculate the mass of acetic acid, use the following
equation. For 5 %, replace 0.04 with 0.050. Record results in
table. You can assume the percent has 2 sig figs.
mass of acetic acid = mass of vinegar x 0.040
9. Determine the molar mass of acetic acid, HC2H3O2.
10. Determine the number of moles of acetic acid in each
sample of vinegar. Hint: you need to use the mass of acetic
acid, not the mass of vinegar.
11. Add the mass of baking soda and vinegar initially. This is
the total initial mass of reactants.
12. Record the final mass of mixture.
13. Determine the total mass gain or loss for the reaction by
comparing your initial mass to the final mass of mixture. This
is the mass of carbon dioxide lost which is your actual loss.

4. 14. Compare the moles of sodium bicarbonate to moles of acetic
acid. Which one is the limiting reactant and why? Show
calculations to support this but also describe what you saw that
supports your statement.
15. Determine the number of grams of carbon dioxide that the
reaction should theoretically produce. This is where the pen
and paper stoichiometry comes in. In the calculation, use the
limiting reactant as your "known" and the carbon dioxide as
your unknown. You have already calculated the moles of
sodium bicarbonate and acetic acid used so Step I in the “three
steps process” used to go from grams known to grams unknown
is already done. See the Ch. 8 Lecture about Steps II and III,
remembering that one mole of acetic acid or sodium bicarbonate
should produce one mole of carbon dioxide (from Eq #7).
16. Calculate the “percent yield” for the carbon dioxide
produced. If the actual yield is a negative number, then the %
yield would be 0.
Be careful of sig figs in your calculations. Make sure you
showed work.
Questions
17. Look at the percent yield of carbon dioxide produced. Give
a possible cause (experimental error, not calculation or
measurement or instrumental error) for differences between
what you calculated should be produced (theoretical yield) and
what was actually produced. This should be something that you
probably couldn’t avoid very well. (So don’t say, “I measured
wrong” or “I calculated wrong” because this is easily avoidable
by redoing the lab or re-measuring).
18. In the calculation for #15, why couldn’t the moles of the
other reactant be used in the calculation?

5. 19. True or False: After you figure out the moles of the
reactants in a reaction, the lower amount of moles is always the
limiting reactant. Please explain your answer thoroughly.
Providing an example would be very helpful.
Keep going on the next page
Extension with calcium carbonate:
Suppose we did the quantitative experiment part 2 with calcium
carbonate (found in egg shells and Tums) instead of baking
soda. So we reacted it with vinegar and took mass
measurements.
20. Write a balanced reaction for acetic acid reacting with
calcium carbonate. Be careful. It is no longer a 1:1 ratio. Hint:
you should’ve written this in words in #2 so now turn those
words into correct formulas and balance. Include phases.
21. Suppose we got the following data from doing the lab with
vinegar and calcium carbonate. Fill in the 2 missing boxes (with
the green stars **) using the given data.
Data Table
Run #1
Mass calcium carbonate (alone)
3.9 g
Mass beaker
30.0 g
Vinegar percent
5%
Mass vinegar + beaker
84.2 g
Mass vinegar (alone)
**
Mass mixture + beaker after reaction

6. 87.4 g
Mass mixture (only) after reaction
**
Calculations (Show all work by each question below the table
and then enter the final results of each calculation into the
following table)
Results (show work below)
Run #1
22. Molar mass of calcium carbonate
23. Moles of calcium carbonate
24. Mass of acetic acid in vinegar
25. Molar mass of acetic acid
26. Moles of acetic acid
27. Total initial mass
28. Final mass mixture (measured in lab – copy from above
table)
29. Difference in mass = initial mass – final mass = carbon
dioxide produced (actual yield)
30. Limiting Reactant
31. Theoretical yield carbon
dioxide
32. % yield carbon dioxide

7. 22. Determine the molar mass of calcium carbonate (using a
periodic table).
23. Calculate the number of moles of calcium carbonate using
the data above.
24. Determine the mass of acetic acid used in the experiment.
Assume vinegar is 5% on the bottle. (If it is 5 %, then 100 g
contains 5 g of acetic acid). Record results in table below. You
can assume the percent has 2 sig figs.
25. Determine the molar mass of acetic acid, HC2H3O2. No
need to show work here if you did above. Just put it in the table.
26. Determine the number of moles of acetic acid in the sample
of vinegar that was used. Hint: you need to use the mass of
acetic acid, not the mass of vinegar.
27. Add the mass of calcium carbonate and vinegar initially.
This is the total initial mass of mixture. Record results.
28. The final mass of the mixture is given in the table above.
Just report this number below (no work to show).
29. Determine the total mass gain or loss for the reaction by
comparing your initial mass to the final mass of mixture. This
is the mass of carbon dioxide lost which is your actual loss.
30. To determine the number of grams of carbon dioxide that
the reaction should theoretically be produced, we need to first
determine the limiting reactant. This is where the pen and paper
stoichiometry comes in. Compare the moles of calcium
carbonate to acetic acid. Which one is the limiting reactant and
why? ** Be very careful** This is not a 1:1 ratio like the first
part of the lab.

8. 31. Determine the theoretical yield of carbon dioxide. To do
this, in the calculation, use the limiting reactant as your known
and the carbon dioxide as your unknown. You have already
calculated the moles of calcium carbonate and acetic acid used
so Step I in the “three steps process” used to go from grams
known to grams unknown is already done. See the Ch. 8
Lecture about Steps II and III, but remember that now we do not
have a 1:1 ratio.
32. Calculate the “percent yield” for the carbon dioxide
produced. If the actual yield is a negative number, then the %
yield would be 0.
Extra Credit Questions:
a) In this particular example, the change in mass during the
reaction provides evidence that a chemical reaction is taking
place. Explain this.
b) Is it necessary to have a change in mass in order to have a
chemical reaction? Why or why not?
c) Provide an example of a chemical reaction (not just a
physical change) where no mass change would be observed.