Question & Answer: A solution is found to be 0.0942% by weight CoCl_3. What is the concentration of the Cl^1- ion…..

0.0942%by weight of CoCl3 means 0.0942 g of CoCl3 present in 100ml of Solution

molarity = W*1000/G.M.Wt * volume of solution ml

= 0.0942*1000/165.3*100   = 0.0057M

CoCl3 —————> Co^3+ (aq) + 3Cl^-

0.0057M                                        3*0.0057M

conc of Cl^-   = 3*0.0057M    = 0.0171M   = 0.0171*35500   = 607.05ppm             [ 1M = 35500ppm]