[Moronic_Acid]

Exam question on a past paper got the exam tomorrow i know its probably quite easy but i don't know where to start any help would be appreciated.

two solutions, each at the same temperature (298 K).
SOLUTION 1: calcium hydrogen phosphate (CaHPO4) dissolved in water;
SOLUTION 2: calcium hydrogen phosphate (CaHPO4) dissolved in a solution
already containing 0.05 M of hydrogen phosphate ions (HPO4)2–

By what factor is the concentration of calcium ions higher in Solution 1 than Solution 2,
given that the solubility product Ksp of calcium hydrogen phosphate is 2.0 x 10(–30) at 298 K?

[sjb]

Exam question on a past paper got the exam tomorrow i know its probably quite easy but i don't know where to start any help would be appreciated.

two solutions, each at the same temperature (298 K).
SOLUTION 1: calcium hydrogen phosphate (CaHPO4) dissolved in water;
SOLUTION 2: calcium hydrogen phosphate (CaHPO4) dissolved in a solution
already containing 0.05 M of hydrogen phosphate ions (HPO4)2–

By what factor is the concentration of calcium ions higher in Solution 1 than Solution 2,
given that the solubility product Ksp of calcium hydrogen phosphate is 2.0 x 10(–30) at 298 K?

Well, for starters, what is the solubility of pure calcium hydrogen phosphate in distilled water?