Question

a 1.00-L solution saturated at 25°C with calcium oxalate (CaC2O4) contains 0.0061 g of CaC2O4. The solubility constant (Ksp) for this salt is [CaC2o4= 128.09 g/mol]

a) 6x10^ -3
b) 4.6x10^ -8
c) 2.3x10^ -9
d) 1.5x10^-4

if you could please work it out for me, thank you

Answer 1

It would have helped if you had written the question properly. SURELY you didn't copy it word for word.
You WANT to solve for the Ksp. The MOLAR MASS is 128.09.
CaC2O4 ==> Ca^+2 + C2O4^-2

Ksp = (Ca^+2)(C2O4^-2) = ??
moles CaC2O4 = 0.0061/molar mass.
Ksp = (Ca^+2)^2 = ??

Answer 2

The question was written properly & I DID it copy word for word. And how you explained it, doesn't help.

Answer 3

Use the moles and get molarity, don't forget you've been given the volume.. then use in solving for Ksp.