Which Salt Produces the Lowest Carbonate Ion Concentration?

[Soaring Crane]

The equilibrium constants are given for the following salts
MgCO3 = 6.8x10-6
CaCO3 = 5.0x10-9
BaCO3 = 2.6x10-9
What is the name of the salt that will produce the lowest concentration of carbonate ion in solution? Write the name not the chemical formula.



Is it barium carbonate?? Is there a direct relationship between carbonate concentration and E_c?

Thanks.

 

[ksinclair13]

Yes, I think you are correct. The lower the Kc value, the more the reactants are favored (equilibrium position is far to the left), which would mean less dissociation, which would yield the lowest concentration of the carbonate ion on the products side.

 

[Borek]

The equilibrium constants are given for the following salts
MgCO3 = 6.8x10-6
CaCO3 = 5.0x10-9
BaCO3 = 2.6x10-9

As worded it doesn't make any sense. There is no such thing as an equilibrium constant for a given substance. There is an equilibrium constant for a given reaction.

You are probably talking about solubility products. If so, you are right.

As for the concentration - write reaction equation, write equation for solubility product. What is relation between concentration of carbonate ion and barium ion? Substitute.