Chemical Composition Eggshell Lab
Alicia Armstrong
Calcium Carbonate Eggshell Lab
Purpose: To determine the percentage of Calcium Carbonate in two different types of eggshells.
Background Information: HCl will react with calcium carbonate turning it into a liquid and the rest of the eggshell that doesn’t react with the HCl will remain solid allowing the egg and the HCl to be separated through a filter process. The remaining eggshell contents are composed of phosphorus and magnesium, and trace amounts of sodium, potassium, zinc, manganese, iron, and copper. Also from doing additional research the average eggshells calcium carbonate mass is 2.2 grams and the average percentage is 77%. And from doing some more additional research the balanced equation for the lab that we were using was
CaCO3 (s) + 2HCl(aq) CaCl2 (aq) + CO2 (g) + H2O(l)
Hypothesis: The brown eggshell will have a higher percentage of CaCO3 then the green eggshell. I get this hypothesis from some research I did and I found out that a brown egg is usually larger then most eggs because it comes from larger hens and that is why brown eggs cost more then other eggs, and when there is a bigger plane to cover then there is a larger amount of the eggshell’s contents which happens to be HCl.
Materials: 25ML Graduate cylinder we used 4. Pipettes. Stirring rod.
Mortal and pestle. Distilled water. Oven. 250 ML Beakers. Funnel.
Filter paper. 250ML flasks. Evaporating dish.
Procedure: This is for my Brown Egg
1. Separate eggshell from yolk, whites, and membrane and let eggshell sit to dry
2. Take eggshell and using the mortal and pestle grind eggshell to a powder
3. Weigh empty evaporating dish record weight: 40 grams
4. Put eggshell powder into dish and weigh it: 45 grams
5. Subtract evaporating dish’s weight from the previous measurement: 5 grams, this is your eggshells weight. Set aside and prepare for HCL.
6. Weigh an empty 25ML graduated cylinder record weight: 36 grams
7. Fill graduated cylinder with 5ML HCl weigh and record weight: 40 grams.
8. Subtract 25ML graduated cylinder’s weight from the previous measurement and record: 4 grams, this is weight is the weight of your HCl. Set aside and get out 250 ML beaker.
9. Weigh 250 ML empty beaker record weight: 95.5 grams
10.Combine eggshell powder with HCL in 250 ML beaker after reaction weigh combination: 105 grams
11.Subtract empty 250-beaker weight from the previous measurement and record: 9.5 grams, this weight is your combination mass of both the HCl and the eggshell powder.
12.Now here is where we got stuck, using the equation above and the knowledge you have with stoichiometry substitute eggshell grams and HCl grams into the equation and calculate both to find the limiting reactant. Our limiting reactant was HCl, when this happens it means you need to add more HCl to the powder to fully get rid of the calcium carbonate
13. CaCO3 (s) + 2HCl(aq) CaCl2 (aq) + CO2 (g) + H2O(l)
14.After adding more HCl and when you are sure that all the calcium carbonate has been reacted, add distilled water to the combination to dilute the acid so you can filter the liquid from the solid
15.Weigh dry clean empty filter paper record weight: 1.010 grams
16.Using a funnel and the filter paper fold paper in half and wrap it around the funnel on the inside
17.Using the funnel and filter paper separate the solid eggshell from the liquid
18.Take out filter paper which should have solid egg contents on it and put in evaporating dish and weigh it, record weight: 46 grams
19.Now from knowing the evaporating dish’s weight subtract that from your previous weight along with the filter papers weight you should get 5 grams this is the weight of the un-reacted eggshell
20.Now because your filter paper is still wet you cant be sure that 5 grams is your un-reacted eggshell’s weight so what you need to do is evaporate the liquid to do this I had to go home and over the weekend I put the filter paper and my eggshell contents in my oven to evaporate all the liquid
21.After liquid is evaporated weigh the eggshell again remember to subtract filter paper weight and record: 3.37 grams
22.To figure out your overall weight loss take the eggshells initial mass which is the mass you recorded before the reaction which was 5 grams, subtract your final mass 3.37grams from 5 grams your result is 1.63 grams which is rounded to 2 grams. Now to find the percentage of your overall loss mass take your result mass 1.63 grams and divide it by your initial mass 5 your answer is .4 which is 40% so your over all percentage of Calcium Carbonate in your eggshell is 40%.
Safety Issues & Other Suggestions
-You will be dealing with 3M HCl acid. HCl is a strong acid and 3M are a high concentration. It has the ability to burn your skin and cause permanent damage to eyes. Your procedure may result in having excess unreacted acid at the end of the experiment. This acid needs to be dealt with and disposed of safely
-You may transport a sample back to AHS and let it dry over the weekend if this would be beneficial
-You should use ½ to ¾ of each type of eggshell
-You should remove the inner membrane from the eggshell before beginning the experiment
Results: This is both the Brown and Green eggshell results the green egg followed the exact same procedure as the brown egg and there was a difference in our overall results here is a table to show the basics of our labs.
Eggshell Color
Initial Mass Before Reaction
Mass after reaction before evaporating process
Mass after evaporating process
Final Mass of Calcium carbonate/eggshell loss
Calcium Carbonate Percentage over all
Brown
5 grams
5 grams
3.37 grams
1.63 grams
40%
Green
4 grams
4 grams
3.84 grams
.16 grams
.025%
Conclusion: The purpose for this lab was to figure out the percentage of Calcium Carbonate there is in two different eggshells, during this lab my partner Izzy and I used a brown eggshell and a green eggshell, from doing some additional research about the two eggs I came up with the hypothesis that my brown eggshell will have a higher percentage of Calcium Carbonate then Izzy’s green eggshell, because brown eggs are larger and they tend to have more eggshell contents then most eggshells and the contents happen to be Calcium Carbonate, as you can see from my results my hypothesis was correct my brown eggshell indeed did have a higher percentage of calcium carbonate then izzy’s green eggshell.
During this experiment we ran into a few problems one was during the reaction process we had to do some additional work using our over all balanced equation above to figure out the limiting reactant in our reaction, we found out that we didn’t use enough HCl as a result we had to add more HCl to fully get rid of our calcium carbonate. Another error that occurred during our lab was some of the eggshell stuck to the beaker when we were doing the filtering process, the loss eggshell effects our results because it makes out calcium carbonate mass/percentage higher as a estimate of how much eggshell was on the beaker I say about 1.5 grams which isn’t a huge difference but its still a difference. The green eggshell somehow resulted in a drastically low amount of calcium carbonate percentage, I wish I could tell you exactly what caused this drastic error but the eggshell endured the exact same procedure as the brown eggshell and well all I can say is somewhere during the procedure there was a miscalculation I can honestly say that I am really stumped on this error.
If I could go back and redo the lab I would most likely keep the same procedure but I would make sure there are no errors on any of the calculations for the eggshells and instead of just adding 5 ML of HCL I would add enough acid so that there is no reaction taking place before I add the water that way I am sure that all of the calcium carbonate is fully reacted. Other than that I am very content with my brown eggshell’s result my mass was 5 grams and my over all mass loss when rounded was 2 grams which according to my additional research is the average eggshell’s calcium carbonate mass so I met the average mass and the average percentage which means that my chickens lay an average egg which is very pleasing, I do wonder though, if feeding my chickens scratch plays a role in my results. Guess that’s something I will have to figure out later. Thank You.
Calcium Carbonate Eggshell Lab
Purpose: To determine the percentage of Calcium Carbonate in two different types of eggshells.
Background Information: HCl will react with calcium carbonate turning it into a liquid and the rest of the eggshell that doesn’t react with the HCl will remain solid allowing the egg and the HCl to be separated through a filter process. The remaining eggshell contents are composed of phosphorus and magnesium, and trace amounts of sodium, potassium, zinc, manganese, iron, and copper. Also from doing additional research the average eggshells calcium carbonate mass is 2.2 grams and the average percentage is 77%. And from doing some more additional research the balanced equation for the lab that we were using was
CaCO3 (s) + 2HCl(aq) CaCl2 (aq) + CO2 (g) + H2O(l)
Hypothesis: The brown eggshell will have a higher percentage of CaCO3 then the green eggshell. I get this hypothesis from some research I did and I found out that a brown egg is usually larger then most eggs because it comes from larger hens and that is why brown eggs cost more then other eggs, and when there is a bigger plane to cover then there is a larger amount of the eggshell’s contents which happens to be HCl.
Materials: 25ML Graduate cylinder we used 4. Pipettes. Stirring rod.
Mortal and pestle. Distilled water. Oven. 250 ML Beakers. Funnel.
Filter paper. 250ML flasks. Evaporating dish.
Procedure: This is for my Brown Egg
1. Separate eggshell from yolk, whites, and membrane and let eggshell sit to dry
2. Take eggshell and using the mortal and pestle grind eggshell to a powder
3. Weigh empty evaporating dish record weight: 40 grams
4. Put eggshell powder into dish and weigh it: 45 grams
5. Subtract evaporating dish’s weight from the previous measurement: 5 grams, this is your eggshells weight. Set aside and prepare for HCL.
6. Weigh an empty 25ML graduated cylinder record weight: 36 grams
7. Fill graduated cylinder with 5ML HCl weigh and record weight: 40 grams.
8. Subtract 25ML graduated cylinder’s weight from the previous measurement and record: 4 grams, this is weight is the weight of your HCl. Set aside and get out 250 ML beaker.
9. Weigh 250 ML empty beaker record weight: 95.5 grams
10.Combine eggshell powder with HCL in 250 ML beaker after reaction weigh combination: 105 grams
11.Subtract empty 250-beaker weight from the previous measurement and record: 9.5 grams, this weight is your combination mass of both the HCl and the eggshell powder.
12.Now here is where we got stuck, using the equation above and the knowledge you have with stoichiometry substitute eggshell grams and HCl grams into the equation and calculate both to find the limiting reactant. Our limiting reactant was HCl, when this happens it means you need to add more HCl to the powder to fully get rid of the calcium carbonate
13. CaCO3 (s) + 2HCl(aq) CaCl2 (aq) + CO2 (g) + H2O(l)
14.After adding more HCl and when you are sure that all the calcium carbonate has been reacted, add distilled water to the combination to dilute the acid so you can filter the liquid from the solid
15.Weigh dry clean empty filter paper record weight: 1.010 grams
16.Using a funnel and the filter paper fold paper in half and wrap it around the funnel on the inside
17.Using the funnel and filter paper separate the solid eggshell from the liquid
18.Take out filter paper which should have solid egg contents on it and put in evaporating dish and weigh it, record weight: 46 grams
19.Now from knowing the evaporating dish’s weight subtract that from your previous weight along with the filter papers weight you should get 5 grams this is the weight of the un-reacted eggshell
20.Now because your filter paper is still wet you cant be sure that 5 grams is your un-reacted eggshell’s weight so what you need to do is evaporate the liquid to do this I had to go home and over the weekend I put the filter paper and my eggshell contents in my oven to evaporate all the liquid
21.After liquid is evaporated weigh the eggshell again remember to subtract filter paper weight and record: 3.37 grams
22.To figure out your overall weight loss take the eggshells initial mass which is the mass you recorded before the reaction which was 5 grams, subtract your final mass 3.37grams from 5 grams your result is 1.63 grams which is rounded to 2 grams. Now to find the percentage of your overall loss mass take your result mass 1.63 grams and divide it by your initial mass 5 your answer is .4 which is 40% so your over all percentage of Calcium Carbonate in your eggshell is 40%.
Safety Issues & Other Suggestions
-You will be dealing with 3M HCl acid. HCl is a strong acid and 3M are a high concentration. It has the ability to burn your skin and cause permanent damage to eyes. Your procedure may result in having excess unreacted acid at the end of the experiment. This acid needs to be dealt with and disposed of safely
-You may transport a sample back to AHS and let it dry over the weekend if this would be beneficial
-You should use ½ to ¾ of each type of eggshell
-You should remove the inner membrane from the eggshell before beginning the experiment
Results: This is both the Brown and Green eggshell results the green egg followed the exact same procedure as the brown egg and there was a difference in our overall results here is a table to show the basics of our labs.
Eggshell Color
Initial Mass Before Reaction
Mass after reaction before evaporating process
Mass after evaporating process
Final Mass of Calcium carbonate/eggshell loss
Calcium Carbonate Percentage over all
Brown
5 grams
5 grams
3.37 grams
1.63 grams
40%
Green
4 grams
4 grams
3.84 grams
.16 grams
.025%
Conclusion: The purpose for this lab was to figure out the percentage of Calcium Carbonate there is in two different eggshells, during this lab my partner Izzy and I used a brown eggshell and a green eggshell, from doing some additional research about the two eggs I came up with the hypothesis that my brown eggshell will have a higher percentage of Calcium Carbonate then Izzy’s green eggshell, because brown eggs are larger and they tend to have more eggshell contents then most eggshells and the contents happen to be Calcium Carbonate, as you can see from my results my hypothesis was correct my brown eggshell indeed did have a higher percentage of calcium carbonate then izzy’s green eggshell.
During this experiment we ran into a few problems one was during the reaction process we had to do some additional work using our over all balanced equation above to figure out the limiting reactant in our reaction, we found out that we didn’t use enough HCl as a result we had to add more HCl to fully get rid of our calcium carbonate. Another error that occurred during our lab was some of the eggshell stuck to the beaker when we were doing the filtering process, the loss eggshell effects our results because it makes out calcium carbonate mass/percentage higher as a estimate of how much eggshell was on the beaker I say about 1.5 grams which isn’t a huge difference but its still a difference. The green eggshell somehow resulted in a drastically low amount of calcium carbonate percentage, I wish I could tell you exactly what caused this drastic error but the eggshell endured the exact same procedure as the brown eggshell and well all I can say is somewhere during the procedure there was a miscalculation I can honestly say that I am really stumped on this error.
If I could go back and redo the lab I would most likely keep the same procedure but I would make sure there are no errors on any of the calculations for the eggshells and instead of just adding 5 ML of HCL I would add enough acid so that there is no reaction taking place before I add the water that way I am sure that all of the calcium carbonate is fully reacted. Other than that I am very content with my brown eggshell’s result my mass was 5 grams and my over all mass loss when rounded was 2 grams which according to my additional research is the average eggshell’s calcium carbonate mass so I met the average mass and the average percentage which means that my chickens lay an average egg which is very pleasing, I do wonder though, if feeding my chickens scratch plays a role in my results. Guess that’s something I will have to figure out later. Thank You.