You are given a solution of the following cations in water: Ag+, Co2+, Ba2+, Zn2+, and Sn2+. You want to separate the ions out one at a time by precipitation using the following reagents: NaF, NaI, Na2SO4, and NaCl.
a. In what order would you add the reagents to ensure that only one cation is precipitating out at a time?
b. Why are the anionic reagents listed above all sodium salts?