Barium iodate, Ba(IO), has a solubility product K = [Ba][IO] = 1.57 x 10. Its solubility in pure water is 7.32 x 10 M. However in a solution that is 0.0200 M in barium nitrate, Ba(NO), the increase in the common ion barium leads to a decrease in iodate ion concentration. The solubility is therefore reduced to 1.40 x 10 M, about five times smaller.