Question

Determine the solubility of silver chromate at 298 K given its K_sp value is 1.1 × 10^-12.

• A. 6.5 × 10^-5
• B. 2.4 × 10^-2
• C. 3.6 × 10^-3
• D. 8.9 × 10^-4

Answer 1

Answer: (A)

$\text{Ag}_{2} \text{CrO}_{4} \rightleftharpoons \text{2Ag}^{+} + \text{CrO}_{4}^{2 -} \text{;} \text{K}_{\text{sp}} = \text{1.1} \times \text{10}^{- \text{12}}$

S 2S S

$\text{K}_{\text{sp}} = \left[\text{Ag}^{+}\right]^{2} \cdot \left[\text{CrO}_{4}^{2 -}\right]$

K_sp = [2S]² · [S] = 4S³

$\text{S}^{3}= \, \frac{K_{sp}}{4} \, = \, \frac{1.1 \times 10^{- 12}}{4}$

$\Longrightarrow \text{S}=6.53\times 10^{- 5}$