Essay On Back Titration

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Synopsis The objective of this experiment is to demonstrate quantitative transfer of solids and liquids, performing and familiarizing with back titration for the determination of calcium carbonate (CaCO3) in toothpaste. Back titration is used when the substance being analyzed is volatile, partially or completely insoluble in water. In this experiment, our main objective is to determination of the percentage of calcium carbonate (CaCO3) in toothpaste. As calcium carbonate is insoluble in water, direct titration method is not suitable for this experiment. Back titration has to be carried out to determine the percentage of calcium carbonate in toothpaste instead. This experiment will be performed on the calcium carbonate in toothpaste, HCl solution…show more content…
The concentration of an analyte can be determined by reacting it with a known number of moles of excess reagent using back titration. The excess reagent is then titrated with the second reagent. The concentration of the analyte in the original solution is then calculated by the amount of reagent needed to react completely. Back titration is used when the substance analyzed is volatile, partially insoluble or completely insoluble in water. In this experiment, our main objective is to determination of calcium carbonate (CaCO3 in toothpaste). As calcium carbonate is insoluble in water, direct titration method is not suitable for this experiment and back titration has to be carried out to determine the percentage of calcium carbonate in toothpaste instead of direct titration. When calcium carbonate is added to any acid, it will produce salt, water (H2O) and carbon dioxide (CO2) Basically titration carried out in reverse is known as a back titration. Instead of titrating the original sample of calcium carbonate in toothpaste, a known excess of 0.1640 M HCl solution is added to the toothpaste containing calcium carbonate in order to dissolve it. The excess of 0.1640 M of HCl is then titrated by 0.08625 M NaOH solution as shown
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