Question

Chlorine in H2O is tested byadding silver ions to make silver(i)chloride which is insoluble. How much chloride is in a sample of water if it took 20.2ml of a 0.100 M Ag(no3) solution to react all of the chlorine?

Answer 1

AgNO3 + Cl- ---------------------> AgCl + NO3-

moles of AgNO3 = moles of Cl-

moles of AgNO3 = 20.2 x 0.1 / 1000

                         = 2.02 x 10^-3

moles of Cl- = 2.02 x 10^-3

mass of Cl- = 2.02 x 10^-3 x 35.5

                    = 0.0717 g

mass of chloride in the sample = 0.0717 g