[Emical]

I need help on a titration problem. I don't know where to start and I would appreciate any help I could get! Please don't give me false answers or help either, chemistry isnt my best subject and im really trying to learn..
Here is the problem":
The analysis of chloride in water is often performed using the Mohr titration.  This is a precipitation titration in which chloride is titrated with silver nitrate, a reaction occurs and the chloride forms a white silver chloride precipitate (AgCl  Ksp = 1.8 x 10-10).  The equivalence point of the titration is detected by adding chromate ion which causes orange Ag2CrO4 (Ksp = 1.2 x 10 -12) to  precipitate at the end point.  The way this works, is that the silver chromate is more soluble that the silver chloride, so as the silver nitrate is added the chloride eventually gets low enough for the chromate to precipitate and make the solution turn orange at the end point.  If you add 1.0 x 10-2  M CrO42- to the titration, what is the Cl-  concentration at the end point of the titration?

Please *delete me*

[AWK]

From Ksp of K2CrO4 you can deterrmine a molar concentration of Ag+ at the end point, ant then from this concentration and Ksp of AgCl you can calculate concentration of Cl-.