Experiment of Calcium Carbonate Composition of Eggshells

Experiment of Calcium Carbonate Composition of Eggshells INTRODUCTION Calcium carbonate, CaCO3, is found in nature giving hardness and strength to things such as seashells, rocks, and eggshells. As hard as this substance is, it will react readily with hydrochloric acid to yield carbon dioxide gas (and two other products). In this experiment students will design an experiment by reacting eggshells with 2 M HCl to compare the calcium carbonate composition of white (chicken) eggshells to brown eggshells. A good quality eggshell will contain, on average, 2.2 grams of calcium in the form of calcium carbonate. Approximately 94% of a dry eggshell is calcium carbonate and has a typical mass of 5.5 grams,1 although these values can differ depending on sources. Amounts as low as 78% have been published. The remaining mass is composed largely of phosphorus and magnesium, and trace amounts of sodium, potassium, zinc, manganese, iron, and copper. In the case of brown versus white eggs, a definitive difference in calcium carbonate amounts may be hard to uncover. However, consider this. The color of the eggs is nothing more than a result of a different breed. The quality, nutritional value, and taste are identical between white and brown eggs, though two notable differences are size and price. Brown eggs are usually larger and slightly more expensive. The reason for the price increase is because brown eggs come from larger hens, which need to be fed more food daily. With a larger intake of calci um each day, one might expect the produced egg to have a higher calcium carbonate content. However, since the eggs are larger, it must be kept in mind that the calcium is spread over a larger surface area during egg formation. A brown eggshells increased tendency to break, when compared to white, is often attributed to this â€Å"thinning out† of calcium during deposition. To avoid the breakage of eggs before reaching market, the eggshells needs to be as strong as possible. The strength of eggshells is mainly determined by the percentage of calcium carbonate in it. In order to monitor the quality of eggshells, the following experiment has to be done to determine the percentage of calcium carbonate in eggshells. In this experiment, back titration is used. First, excess acid is reacted with the calcium carbonate in eggshells. 2HCl(aq)+CaCO3(s)→CaCl2(aq)+H2O(l)+CO2(g) Later, if we can find out the number of mole of unreacted acid, number of mole of calcium carbonate can then be found out. The number of mole of unreacted acid can be found by titration with the following reaction. HCl(aq)+NaOH(aq)→H2O(l)+NaCl(aq) Percentage by mass of calcium carbonate in eggshell can then be calculated by the following formula: 4.2AIMS AND OBJECTIVES The purpose of this experiment is to determine the percentage by mass of calcium carbonate in eggshells. design an experiment that quantifies the amount of calcium carbonate present in a natural substance. relate the amount of a reactant or product of a chemical reaction to another reactant or product. work collaboratively with their peers to solve a given problem in the laboratory in a way that models the scientific method. apply a common acid reaction between hydrochloric acid and the carbonate ion. Chapter 2 THEORY METHOLOGY PRINCIPLE OF THE EXPERIMENT During this experiment, the percentage of CaCO3 in an eggshell is determined by reacting the eggshell with hydrochloric acid. The equation for this reaction is: 2HCl (aq) + CaCO3(s)→Ca2+ (aq) + CO2 (g) + H2O (l) + 2Cl- (aq) This reaction cannot be used directly titrate with the CaCO3. Instead, an excess of hydrochloric acid is added to dissolve the eggshell, and the remaining acid is titrated with NaOH solution to determine the amount of acid that did not react with the eggshell. The equation used to determine the amount of leftover acid is: HCl (aq) + NaOH (aq) → H2O (l) + Na+ (aq) + Cl- (aq) APPARATUS AND EQUIPMENTS Beaker Pipette Filler Electronicbalance Volumetric flask BuretteWash bottle Mortar and pestle Conical flasks White tile Filter funnel Filtter paper 25.00 cm 3 pipette CHEMICALS USED 2 M HCl Phenolphthalein 2 M NaOH PROCEDURE White and Red colour eggshells have taken and the protein membrane was removed on the inside of the eggshells. The eggshell was washed with distilled water Dried in an oven for few minutes. The eggshell was then grounded into fine powder by mortar and pestle. 2g of eggshell powder is weighted accurately by using an electronic balance and it was transferred to a conical flask. 25.00 cm3 of HCl was pipetted to dissolve the eggshell powder. Distilled water was added to the flask until it reached about 100cm3. The flask was swirled gently. Put the solution into cubed for two days. Faltered the solution using filter papers. Pippet out 25.00 cm3 from each solutions to titration flasks. The solution was then titrated with standardized NaOH. Repeat another two samples from each solution. Collect the correct burette readings at the end point. Chapter 3 EXPERIMENTAL RESULTS THE COLOR CHANGE OF THE SOLUTION White egg Brown egg Colourless pink Colourless pink THE TITRATION RESULT OF BROWN EGG 1 2 3 Volume of eggshells solution/cm3 25.00 25.00 25.00 Volume of NaOH used/cm3 20.10 19.90 20.10 Average volume of NaOH used: (20.10+19.90+20.10) = 20.03cm33 THE TITRATION RESULT OF WHITE EGG 1 2 3 Volume of eggshells solution/cm3 25.00 25.00 25.00 Volume of NaOH used/cm3 20.40 20.35 20.00 *Average volume of NaOH used: (20.40+20.35+20.00) =20.25cm33 Chapter 4 CALCULATIONS CALCULATIONS 2HCl (aq) + CaCO3(s)→Ca2+ (aq) + CO2 (g) + H2O (l) + 2Cl- (aq) HCl (aq) + NaOH (aq) → H2O (l) + Na+ (aq) + Cl- (aq) FOR BROWN EGG Number of moles of NaOH used to react with HCl =20.03cm3 /1000) X2M = 40.06X 10-3 mol Since number of moles of NaOH = number of moles of HCl in 25cm3 =40.06 X 10-3 mol HCl mols in 100cm3 = 40.06 X 10-3 X 4 mol The initial no of moles of HCl: volume X molarity = 100/1000 X2M = 200X10-3 mol Number of moles of HCl used to react with CaCO3 = ( 200X10-3 160.24X 10-3) mol = 39.76X10-3 mol According to the equation, one mole of HCI required to react with 2 moles of CaCO3, Number of moles of CaCO3 reacted =39.76X10- 3 /2 = 19.88X10-3 mol The weight of CaCO3 = 19.88X10-3g X100g The % of CaCO3 in eggshell (brown) = (1.988/2) X100% =99.4% FOR WHITE EGG Number of moles of NaOH used to react with HCl: (20.25cm3/1000)X2 = 40.50X10-3mol Since number of moles of NaOH=number of moles of HCl in 25cm3 = 4.50X10-3mol HCl Volume in 100cm3 = 40.50 X10-3 X4 mol The initial moles of HCl: volume X molarity = 100/1000 X2M = 200X10-3 mol Number of moles of HCl used to react with CaCO3 : ( 200X10-3 162X10-3) mol = 38X10-3 mol Number of moles of CaCO3 reacted =38X10-3/2 = 19X10-3 mol The weight of CaCO3 = 19X10-3g X100 The % of CaCO3 in eggshell (white) = (1.9/2) X100% =95.0% Chapter 5 DISCUSSION AND CONCLUTION CONCLUSION Percentage of CaCO3 in red eggshells= 99.4% Percentage of CaCO3 in white eggshells= 95.0% Therefore red eggshells has the higher percentage of CaCO3. DISCUSSION Source of errors The eggshell powder did not dissolve completely Variation in visual judgment at the end point Instrumental errors of the electronic balance The eggshell was not fully dried Some droplets of solution may still adhere on the beaker and the glass rod which lead to the reduction in number of moles of excess HCl In this Experiment we can also do the EDTA titration. REFERENCES http://www.google.lk/search?hl=ensource=hpq=caco3+percentage+in+eggshellbtnG=Google+Searchmeta=aq=foq= http://wwwchem.csustan.edu/chem1102/Egg.htm http://www.oppapers.com/essays/Determine-Percentage-Mass-Calcium-Carbonate-Eggshells/165593 http://ag.ansc.purdue.edu/poultry/multistate/koelkebeck1.htm

Kildress

We have developed food waste profiles for 25 of our most frequently purchased food products. These profiles highlight the percentage of total food production wasted at every stage of the value chain. Below is a selection of these profiles and a summary of how we are tackling the food waste hotshots.Potatoes To reduce losses in the field and processing we are: Reviewing waste alongside customer preferences when selecting different potato varieties using satellite and aerial mapping technology to identify specific trends In lied losses ‘Introducing new technology to remove stones earlier In processing to reduce damage To help customers reduce food waste in the home we are reviewing opportunities for modified atmosphere packaging which could help the potatoes to last longer.Field losses 9%, Processing losses 6%, Retail waste 1%, Consumer waste 39% Illustration of potatoes Cheese To help reduce the amount of cheese our customers waste at home we have: Introduced re-sellable packagi ng on all British cheddar standardized the on-pack shelf life Information so that customers know, for example, that all soft and blue cheeses should be used within three days of opening Added recipes on our Real Food website to provide ways for customers to use up any leftover cheese Field losses 1%, Processing losses under 1%, Retail waste under 1%, Consumer waste Illustration of a cheese board Lamb transporting lamb to improve product quality and freshness. To increase shelf life for customers we are rolling out specialized packaging. This genealogy has been successfully introduced for beef, giving customers up to an extra five days to consume the product, and we hope it will have a similar impact for lamb. Field losses 7%, Processing losses 13%, Retail waste 1%, Consumer waste 5% Illustration of lamb Within the scope of KEMP Alp's limited assurance opinion see page 42 for more details. * Since we published our first five food waste profiles in October 2013, WRAP has published rev ised household food waste data which has been incorporated into our 25 food waste profiles.

The Appeal of History Extended Essay Topics

The Appeal of History Extended Essay Topics The best method is to check through some excellent extended essay examples. You might believe that it is only the cover of your essay, but it's an important component, and you need to treat it correctly. Therefore, if there's any reason why you cannot have your extended essay written on time yourself, all you have to do is place your order on our site, and leave the rest to us! A protracted essay is a kind of academic writing assignment, which success rides on the structure. If you are concerned about formatting your essay and you aren't sure of some things, then do read on. You should note an elongated essay format demands an article of 4000 words. This list of the most intriguing topics is intended to get you inspired. Optionally, you may choose to incorporate an appendices page also. Whether there are only two books that have any connection to your topic, it could be too narrow. If you would like enable more quickly you could always use our custom composing service. You have to come up with your question depending on your subject and the primary theme. The principal issue is all about creating a different page along with all the sources of quotes utilised in your extended essay. What You Must Know About History Extended Essay Topics If your school isn't one already, learn to develop into an IB World School to be able to implement the DP. If you're told to locate a good one on your own, it can be challenging. Students lead busy lives and frequently forget about a coming deadline. As an important part of the International Baccalaureate Diploma Program, some students may choose to get expert support from professional writing services like EWritingService.com. History essays can't center on subjects that occurred in the last ten years that's simply not hist ory. The essay question ought to be evidently mentioned in the essay introduction. You won't be able to crank out a 4,000-word essay in a week and receive an A. Everyone would like to write a fantastic Extended Essay, but just bear in mind that it's really much less overwhelming as it sounds. Besides them, you'll find numerous essay topic generators that may give you interesting ideas. An excellent history essay topic is a lot more important than you could think. As everyone probably knows, simply because you've got a definition essay topic and a couple examples doesn't indicate you've got an essay. Be sure to choose an intriguing subject. Because the elongated essay contains far more words than a typical essay, the selection of topic has to be such a good argument can be developed and resolved. Among other requirements for the protracted essay, there's a point about topics. The selection of topic is all-important in regards to writing an elongated essay and certainly in the topic of history. Make certain you are conversant with the topic. For this reason, you must avoid questions that result in a narrative reaction. Following that, you could also tackle sleeping disorders and offer information regarding effective therapy or cure. The very best advice I can provide you is start early and select your research question carefully. Your answers can help you identify any issues, so that you can then find methods to solve them. Sorry if you were searching for specific topic ideas. Ensure your subject of choice is specific. It will motivate you to produce a good work. If you're really stuck trying to discover a not too broad or narrow topic, I suggest attempting to brainstorm a topic that employs a comparison.

Many Views of Melvilles Bartelby The Scrivener Essay

All literary works are written from a specific standpoint. This standpoint originates from the mind of the author. The author, when creating his literary work, has a specific diagram/plan and vision of what the story is supposed to convey. However, not all readers will interpret the literary work in the way that the author him/herself has presented it. Many times, in fact, the audience will perceive the literary work as having an entirely different meaning than what it was meant to have. The short story, Bartelby the Scrivener by Herman Melville, has been reviewed by several different critics as having several different standpoints. These standpoints include Bartelby as a Psychological Double to the Narrator, an apostle of†¦show more content†¦The narrator, confidently from the very introduction of Bartelby’s character, describes his every move and demeanors as if it was his own. He is able to successfully convey to the unidentified audience who Bartelby is, while managing to leave room for mystery within the character. The familiarity in the narrator’s description leads to a sort of justification of Marcus’ theory of the narrator and Bartelby as a â€Å"Psychological Double.† However, in order to successfully justify this theory, I believe that Marcus should have proceeded to convince his audience that the other characters, Turkey, Nippers, and Ginger Nut, are also alter personalities of the narrator. They too were an intricate p art of the narrator’s description. Each of these characters possessed several positive and negative qualities quite familiar to the narrator. I feel that it is inadequate for Marcus to solely choose Bartelby and leave out the other characters as alternate personalities. Critique of Reason The critic, R.K. Gupta, uses â€Å"reason† to justify his standpoint on Melville’s, Bartelby the Scrivener. Gupta writes: â€Å" The unnamed narrator of â€Å"Bartelby, the Scrivener† is an apostle or reason. His outlook on life is clear, unambiguous, and uncluttered by mysticism or imagination. Reason and common sense are his deities, and he looks upon them as infallible guides to human conduct.† (IJ of