The Fe^2+ will precipitate first.
and i'm also confused on second part...
Consider a solution that is 0.022 M in Fe2+ and 0.014 M in Mg+2.
A). If potassium carbonate is used to selectively precipitate one of the cations while leaving the other on solution, which cation will precipitate first? What minimum concentration of K2CO3 will trigger the precipitate first?
B). What is the remAining concentration of the cation that precipitates first, when the other cation begins to precipatate?
2 answers
First look up ksp for both FeCO3 and MgCO3.
FeCO3 ksp=3.07*10^-11
MgCO3 ksp=6.82*10^-6
Which is less soluble? FeCO3 so in a solution it would precipitate first.
How to find K2CO3 concentration?
Fe ksp=[Fe2+][K2CO3]
3.07*10^-11= 0.022*[K2CO3]
Solve for K2CO3
FeCO3 ksp=3.07*10^-11
MgCO3 ksp=6.82*10^-6
Which is less soluble? FeCO3 so in a solution it would precipitate first.
How to find K2CO3 concentration?
Fe ksp=[Fe2+][K2CO3]
3.07*10^-11= 0.022*[K2CO3]
Solve for K2CO3
9 answers