Answer to Question #132126 in General Chemistry for Van Sung

Question

In this experiment the mass of Cu is determined directly by weighting. How will the mass of chloride be determined?

Answer 1

The law of Gravimetric analysis determines the amount of an analyte( the ion being analysed) through measurement of mass. Two compounds are thus compared using an analyte. The Principe behind this analysis is the use of mass of an ion in a pure compound being determined in finding the mass percentage of the same ion in a known quantity of an impure compound.

In gravimetric analysis of chlorine in a compound, the cation must be found which forms an insoluble compound with the chloride. The compound must be pure and easily filtered.

The rule suggests that $Ag^+$ , $Pb^{2+}$ , and $Hg_2^{2+}$ form insoluble chlorides. Silver chloride could thus be used to determine the percentage of $Cl^-$ , because it is insoluble. It's percentage of insolubility is about$99. 9$ percent of the silver converted to $AgCl$ , the compound can be formed pure and easily filtered.