Three solutions are mixed together to form a single solution; in the final solution, there are 0.2 mol Pb1CH3COO)2, 0.1 mol Na2S, and 0.1 mol CaCl2 present. What solid(s) will precipitate?

Verified step by step guidance

1. Identify the ions present in each compound: Pb(CH3COO)2 dissociates into Pb^{2+} and 2CH3COO^-, Na2S dissociates into 2Na^+ and S^{2-}, and CaCl2 dissociates into Ca^{2+} and 2Cl^-.
2. Write down the possible combinations of cations and anions that could form precipitates. These combinations are PbS, CaS, and NaCl.
3. Consult a solubility table to determine the solubility of each potential precipitate. PbS and CaS are generally insoluble, while NaCl is soluble.
4. Determine which of the insoluble combinations will actually precipitate by considering the ion product (Q) and comparing it with the solubility product (Ksp) for each compound.
5. Conclude that the solids that will precipitate from the solution are those where the ion product exceeds the solubility product, which are likely PbS and CaS based on typical solubility rules.

Key Concepts

Solubility Product Constant (Ksp)

The solubility product constant (Ksp) is a numerical value that represents the equilibrium between a solid and its ions in a saturated solution. It is specific to a particular salt and temperature. When the product of the concentrations of the ions in a solution exceeds the Ksp, a precipitate will form. Understanding Ksp is essential for predicting whether a solid will precipitate when different solutions are mixed.

Precipitation Reactions

Precipitation reactions occur when two soluble salts react in solution to form an insoluble solid, known as a precipitate. This process is driven by the formation of a compound that has low solubility in water. Identifying potential precipitates involves recognizing the ions present in the mixed solutions and determining if they can combine to form an insoluble compound.

Ionic Equilibrium

Ionic equilibrium refers to the state in which the concentrations of ions in a solution remain constant over time, despite ongoing processes of dissolution and precipitation. In the context of mixing solutions, it is crucial to analyze the concentrations of ions and their interactions to predict the formation of precipitates. This concept helps in understanding how the presence of different ions can shift the equilibrium and lead to the formation of solid products.