What are the dissociation equation and Ksp expression for AgCrO4?

Answer 1

Ksp = [Ag+]*[CrO4-] in an equilibrium condition with undissolved AgCrO4 present (saturated solution). From this you can determine the max amount of the compound that will dissolve.

The dissociation constant is used when the solution is not necessarily saturated and Ag+ and CrO4- exist in equilibrium with un-ionized AgCrO4 in solution.

Kd = [Ag+]*[CrO4-] / [AgCrO4]

Kd applies to compounds that ionize weakly. Some compounds (like HCl) will ionize almost 100% in low concentrations and Kd is not defined for them. The dissociation constant for acids is called Ka, and for bases, Kb