Answer
$ K_{sp} (Ag_2C_2O_4) = (5.3 \times 10^{-12})$
Work Step by Step
1. Write the $K_{sp}$ expression:
$ Ag_2C_2O_4(s) \lt -- \gt 2Ag^{+}(aq) + 1{C_2O_4}^{2-}(aq)$
$ K_{sp} = [Ag^{+}]^ 2[{C_2O_4}^{2-}]^ 1$
2. Determine the ions concentrations:
Notice: Each $Ag_2C_2O_4$ molecule, has 2 $Ag^{+}$ ions, therefore, the concentration of $Ag^{+}$ ions is the double of the $Ag_2C_2O_4$ molecules:
$[Ag_2C_2O_4] * 2 = [Ag^+]$
$[Ag_2C_2O_4] * 2 = 2.2 \times 10^{-4}$
$[Ag_2C_2O_4] = 1.1 \times 10^{-4}M$
$[Ag^{+}] = 2.2 \times 10^{-4}$
$[{C_2O_4}^{2-}] = [Ag_2C_2O_4] * 1 = 1.1 \times 10^{-4}$
3. Calculate the $K_{sp}$:
$ K_{sp} = (2.2 \times 10^{-4})^ 2 \times (1.1 \times 10^{-4})^ 1$
$ K_{sp} = (4.84 \times 10^{-8}) \times (1.1 \times 10^{-4})$
$ K_{sp} = (5.324 \times 10^{-12})$
