[MolBio2005]

I've been racking my brain over this and it won't work out, so I created a calibration in order to determine the concentrations in test tubes of Cu²⁺.  This is for Copper II Tartrate, by the way.  I know the overall reaction is CuC₄H₄O₆<->Cu²⁺+C₄H₄O₆.  And therefore the K_sp=[Cu²⁺ ][C₄H₄O₆ ] but from my first two test tubes, where I'm supposed to find the solubility product, I have 0.049M and 0.090 for 1 and 2, respectively.  If I apply the fact that [Cu²⁺ ] and [tartrate] are 1:1 I get two different values for K_sp.  They are different insofar as they would always be different with different [Cu²⁺ ].  I'm wondering if I have to calculate [C₄H₄O₆ ] in another way.  For the first two test tubes I mixed Copper Sulfate and Sodium Tartrate.  I look through every Chemistry resource and I get the same answers leading to my squaring of those concentrations, am I on the right path?

[Borek]

Explain - step by step - what yopu are doing. So far your post doesn't make sense to me.

Note that tartrate anion must be charged.

BTW: forum software breaks when there are two consecutive closing square brackets, separate them with space and your posts will be formatted correctly