Silver chromate is more soluble in solutions containing some(less than 1 M) potassium nitrate, even though neither potassiumnor nitrate show up in the BCE for the dissolution reaction
Ag2CrO4 (s) ↔ 2 Ag+(aq) + CrO4 2-(aq)
The solubility product constant (which is not the same as thesolubility!) for silver chromate is Ksp = 1.1 x 10-12 making it apretty insoluble substance. Your job is to figure out the molarsolubility in pure water, then the molar solubility in a 0.25 MKNO3 aqueous solution and finally to express the change as apercent difference. To make it easier (and faster) please use theDebye-Hückel limiting law: log γx = -0.510 Zx2 (µ)1/2 to obtain therequired activity coefficients and make a simple assumption aboutthe ionic strength of water – rather than solving for it in aniterative process.
