Gravimetric Analysis of a Chloride Salt

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Purpose: To illustrate the chloride amount in a unknown soluble salt with the gravimetric techniques. This also includes the separation of the chloride ion and the silver chloride precipitation. Summary: The unknown sample that is given in the experiment is then dissolved by water and the chloride ion is precipitated as insoluble silver chloride, then the precipitating agent would then be the silver nitrate. AgCl is separated through a process of filtration and thoroughly washing then drying it out to be weighed. Then the content of the chloride in the original salt is then calculated using stoichiometry (Chemistry Department, 2014). Theory: Gravimetric analysis is the measurement of mass, which by definition is categorized into four types however the use of one is only necessary in this experiment, which is precipitation (Gravimetric Analysis, 2012). Therefore the goal is to determine the original amount of ion. This is by isolating the ion in solution by a precipitation reaction, filtering and washing the precipitate free of pollutants, then the conversion of that precipitate to a product of the unknown sample given (Gravimetric Analysis, 2012).Therefore determining the quantitative of that substance by the precipitation reaction. The equation of the precipitate proceeds as follow if followed by the criteria given. The substance must then be fully precipitated. Although in most reactions the precipitate contains very low solubility that losses from dissolution are insignificant. Another thing that effects the reaction is the common ion, which also reduces the solubility of the precipitation method (Gravimetric Analysis, 2012). Ag+(aq) + Cl-(aq) → AgCl(s) The low solubility of AgCl is decreased significantly by the excess of Ag+, which is added causing the equilibrium to move right (Chemistry Department, 2014). If an ice bath is used the
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