1. The problem statement, all variables and given/known data

The k_{sp} values of AgCl and Ag_{2}CrO_{4} are 2*10^{-10} mol^{2}dm^{-6} and 3*10^{-12}mol^{3}dm^{-9} respectively.100cm^{3} of an aqueous solution contains NaCl and K_{2}CrO_{4} only,whose cocentrations are 0.1M and 0.1M respectively.To this solution,is added AgNO_{3} dropwise while mixing.

(1) Calculate and show whether AgCl or Ag_{2}CrO_{4} will be precipitated first?

(2) When the second precipitate begins to appear,what is the concentration of the anion of the Ag salt that precipitated first ,which still remains in the solution?

(3) Using the above answer,explain briefly the accuracy of K_{2}CrO_{4} as an indicator when used in the above titration.

2. Relevant equations

3. The attempt at a solution

I managed to do part (1) of the problem but m having trouble with the rest

since the minimum concentration of Ag+ needed to precipitate AgCl is less than that needed to precipitate Ag chromate,AgCl would precipitate 1st.

(2) I'm not sure I understand the question,

which means the [Ag+] present in the solution is now, 5.477*10^{-6}M,right? but what do I do now?Do I just substitute this value to the ksp equation of AgCl and find the[chloride] in the precipitate and then substract this value from 0.1M?

After all Cl^{-} was precipitated in form of AgCl you still add more solution of AgNO_{3} till the concentration of Ag^{+} is high enough for the Ag_{2}CrO_{4} to precipitate.