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Unknown and Undiluted Titration DateIntroductionDry Chelating agent is dissolved in the nanopure water to make the product that is NA2H2EDTA.2H2O, which is a standard solution. Furthermore the EDTA solution is calculated and analysis has it that, it is 0.0018+-0.00004M.hence the unknown fraction with a factor of 5 is diluted and titrated three times, the total concentration of Mg2+ and Ca2+ was calculated using one of the factor in unknown sample. Notably the total concentration is 0.050+-0.
005M due to calculations. Moreover, the unknown sample is three times titrated hence the concentration of the Ca2+ only, is used to calculate the data that did result to 0.0230+-0.0004M.Furthermore,the concentration of Cca2+ is again subtracted from all the total concentration, in addition the Mg2+ concentration is 0.0227+-0.005M after calculation.Experimental sectionAll the calculation did use Ca/Mg solution of quantity 1.00ml50.00ml of solution under goes dilution in unknown 10.00mlOutcomesStandard EDTA solution concentration After Na2H2EDTA.
2H2O is prepared, and goes in contamination by water in 0.3 wtpercentage the standard solution has to be corrected. Here below are the equations that analyses and further determines the EDTA solution concentration. Mass without impurity is the mass corrected and the mass actual is the dried chelating agent; EDTA concentration bears the name as CEDTA; the initial MW represents molecular weight; and the volume of the solution (500 ml) is V solution. Propagation of the errors calculates the uncertainty.
Balance of uncertainty is +- 0.0001g and that of volumetric flask’s uncertainty is +-0.15 ml. standard relative deviation is initialized by SRD.Calculation of results is in tabulation in the table. Results show that, both relative derivation volume and relative derivation balance is +-0.0003.Moreso, after calculating using the values above EDTA concentration solution is 0.0018+-0.0004M.Unknown sample titration1.00ml Ca/Mg solution in spike is contained in the blank titration, Ph 10 buffer solution, water in conjunction with the indicator.
From all the titration, the data in trial one from all the titrations undergoes nullification due to it being carried out hastily. Additional of 1.00ml in dilution of the unknown sample to the blank titration is put in performance. Equation below is used to calculate V total:Sample of unknown and undiluted titrationSpike solution of1.00ml Ca/Mg, NAOH, water and lastly indicator did perform titration, all-inclusive. Furthermore, the unknown titration bears additional 1.00ml of which in calculates blank titration.
DiscussionUnknown sample concentration of Mg2+ and Ca2+Both the standard deviation and the mean of part one and part two titrations are as follows and in illustration in table 4.Concentration of Mg2+ and Ca2+ can be identified from the values in the unknown sample. Dilution factor will be multiplied with the total concentrations of the calculations results, since the unknown sample is involved in the titration.5 is a dilution factor because 10.00 mL of sample that is unknown is used in the 50.
00 mL volumetric flask.1.00ml is the entire value of Valiquote.Ca2+ concentration calculation as in equations (11) and (12), since the unknown diluted samples is used then there is no dilution factor (Masterton 121). It is pertinent to note that, by subtracting the concentration of the Ca2+ from the resultant concentration, the Mg2+ is found following the example in (13) and (14) equations. Due to propagation of the errors, uncertainties come in and are notable. The numerical values are in illustration in table 5 and represent each equation:0.0049+- 0.0001M results from the unknown samples and the total concentration of Mg2+ and Ca2+.
Ca2+ has the concentration of 0.0032+-0.0003M and 0.0017+-0.0001M is the concentration of Mg2+ . Preparation of standard EDTA solution was in association with uncertainties, pipetting the concentration of the unknown is neglected due to availability of the possibility of ignoring unfair accuracies.Mg2+ to Ca2+ molar ration is 0.5 which is less that 0.1 value. Therefore, there is no significant contamination of the unknown samples.Work cited Masterton , William. Chemistry: Principles and Reactions, 2nd Edition, New York: Cengage Learning, 2009.
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