What is the solubility, in moles per liter, of MgCO₃ (K_sp = 3.5 × 10^-8), in 0.0200 M Na₂CO₃ solution?Hint: Be sure to account for the presence of a common ion. You should also be able to simplify the math because the solubility is very low.

Question

Quizplus · Accepted Answer

The solubility of MgCO₃ is affected by the common ion effect due to the presence of CO₃²⁻ from Na₂CO₃. The solubility product expression is Ksp = [Mg²⁺][CO₃²⁻]. Assuming the solubility of MgCO₃ is 's', [Mg²⁺] = s and [CO₃²⁻] = 0.0200 + s. Since s is very small, [CO₃²⁻] ≈ 0.0200. Thus, Ksp = s(0.0200) = 3.5 × 10⁻⁸, solving for s gives s ≈ 1.8 × 10⁻⁶ M.

What Is the Solubility, in Moles Per Liter, of MgCO3

What Is the Solubility, in Moles Per Liter, of MgCO₃