posted by Mary .
0.12 g of rock salt(NaCl and impurities) was dissolved in water and titrated with 0.1 M silver nitrate. 19.7 mL was required to titrate all the chloride ion. How many moles of sodium chloride were in the original sample and what percent of the sample are impurities?
moles Ag^+ used = M x L = xx.
mols Cl^- in sample = xx.
g Cl^- = mols Cl^- x atomic mass Cl.
0.12 - g Cl = g impurities.