Experiment of Calcium Carbonate Composition of Eggshells

Experiment of atomic number 20 Carbonate Composition of EggshellsINTRODUCTIONCalcium change, CaCO3, is found in character giving votelessness and fortissimo to things such as seashells, rocks, and cuticles. As hard as this substance is, it leave al integrity react readily with hydrochloric stinging to break carbon dioxide gas (and deuce other products). In this experiment students will design an experiment by reacting cases with 2 M HCl to compare the calcium carbonate composition of white (chicken) eggshells to cook 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 muddle of 5.5 grams,1 although these values open fire 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 t he case of dark-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 secret code more than a result of a different breed. The quality, nutritional value, and relishing are identical between white and brown eggs, though twain 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 calcium 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 get up area during egg formation. A brown eggshells increased tendency to break, when compared to white, is oft attributed to this thinning out of calcium during deposition.To avoid the breakage of eggs forwards 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 utilize. First, excess sulphurous is reacted with the calcium carbonate in eggshells.2HCl(aq)+CaCO3(s)CaCl2(aq)+H2O(l)+CO2(g)Later, if we rump find out the number of jetty of unreacted acid, number of gram moleculee of calcium carbonate rotter 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) fate by mass of calcium carbonate in eggshell can then be calculated by the following formula4.2AIMS AND OBJECTIVESThe mean of this experiment is to determine the percentage by mass of calcium carbonate in eggshells.design an experiment that quantifies the amount of calci um carbonate hand over in a naturalsubstance.relate the amount of a reactant or product of a chemical reaction to another reactant or product. motion 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 2THEORY METHOLOGY belief OF THE EXPERIMENTDuring this experiment, the percentage of CaCO3 in an eggshell is determined by reacting the eggshell with hydrochloric acid. The par for this reaction is2HCl (aq) + CaCO3(s)Ca2+ (aq) + CO2 (g) + H2O (l) + 2Cl- (aq)This reaction cannot be use 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 solving to determine the amount of acid that did not react with the eggshell. The equation used to determine the amount of leftover acid isHCl (aq) + NaOH (aq) H2O (l) + Na+ (aq) + Cl- (aq)APPARATUS A ND EQUIPMENTSBeaker Pipette FillerElectronicbalance the great unwashedtric flaskBuretteWash bottle plaster and pestle Conical flasksWhite tileFilter funnelFiltter make-up 25.00 cm3 pipetteCHEMICALS USED2 M HCl Phenolphthalein2 M NaOHPROCEDUREWhite and Red colour eggshells have taken and the protein membrane was removed on the inside of the eggshells.The eggshell was washed with distilled body of waterDried in an oven for few minutes.The eggshell was then grounded into fine gunpowder 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 snowcm3. 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.Repea t another two samples from each solution.Collect the go under burette readings at the end point.Chapter 3EXPERIMENTAL RESULTSTHE COLOR switch OF THE SOLUTIONWhite egg Brown eggColourless criticise Colourless pinkTHE TITRATION RESULT OF BROWN formal123Volume of eggshells solution/cm325.0025.0025.00Volume of NaOH used/cm320.1019.9020.10Average spate of NaOH used (20.10+19.90+20.10) = 20.03cm33THE TITRATION RESULT OF WHITE glob123Volume of eggshells solution/cm325.0025.0025.00Volume of NaOH used/cm320.4020.3520.00*Average volume of NaOH used (20.40+20.35+20.00) =20.25cm33Chapter 4CALCULATIONSCALCULATIONS2HCl (aq) + CaCO3(s)Ca2+ (aq) + CO2 (g) + H2O (l) + 2Cl- (aq)HCl (aq) + NaOH (aq) H2O (l) + Na+ (aq) + Cl- (aq)FOR BROWN EGGNumber of moles of NaOH used to react with HCl=20.03cm3 / meter) X2M = 40.06X 10-3 molSince number of moles of NaOH = number of moles of HCl in 25cm3=40.06 X 10-3 molHCl mols in 100cm3 = 40.06 X 10-3 X 4 molThe initial no of moles of HCl volume X molarity= 1 00/1000 X2M = 200X10-3 molNumber of moles of HCl used to react with CaCO3 =( 200X10-3 160.24X 10-3) mol = 39.76X10-3 mol fit in 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 molThe weight of CaCO3 = 19.88X10-3g X100gThe % of CaCO3 in eggshell (brown) = (1.988/2) X100%=99.4%FOR WHITE EGGNumber of moles of NaOH used to react with HCl(20.25cm3/1000)X2 = 40.50X10-3molSince number of moles of NaOH=number of moles of HCl in 25cm3= 4.50X10-3molHCl Volume in 100cm3 = 40.50 X10-3 X4 molThe initial moles of HCl volume X molarity= 100/1000 X2M = 200X10-3 molNumber of moles of HCl used to react with CaCO3 ( 200X10-3 162X10-3) mol = 38X10-3 molNumber of moles of CaCO3 reacted =38X10-3/2= 19X10-3 molThe weight of CaCO3 = 19X10-3g X100The % of CaCO3 in eggshell (white) = (1.9/2) X100%=95.0%Chapter 5DISCUSSION AND CONCLUTIONCONCLUSIONPercentage of CaCO3 in red eggshells= 99.4%Percentage of CaCO3 in white eggsh ells= 95.0%Therefore red eggshells has the higher percentage of CaCO3.DISCUSSION origination of errorsThe eggshell powder did not dissolve completelyVariation in visual judgment at the end pointInstrumental errors of the electronic balanceThe eggshell was not fully driedSome droplets of solution may still adhere on the beaker and the glass rod which fall out to the reduction in number of moles of excess HClIn this Experiment we can also do the EDTA titration.REFERENCEShttp//www.google.lk/search?hl=ensource=hpq=caco3+percentage+in+eggshellbtnG=Google+Searchmeta=aq=foq=http//wwwchem.csustan.edu/chem1102/Egg.htmhttp//www.oppapers.com/essays/Determine-Percentage-Mass-Calcium-Carbonate-Eggshells/165593http//ag.ansc.purdue.edu/ fowl/multistate/koelkebeck1.htm