You know that an unlabeled bottle contains an aqueous solution of one of the following: AgNO3,CaCl2, or Al2(SO4)3. You take a portion of the solution and add an aqueous solution of Ba(NO3)2 to it, and observe that a white solid precipitates Then you take another portion of the unlabeled solution and add an aqueous solution of NaCl to it; nothing appears to happen. What is the most likely identity of the solution in the unlabeled bottle: silver nitrate, calcium chloride, aluminum sulfate?

Key Concepts

Precipitation Reactions

Precipitation reactions occur when two soluble salts react in solution to form an insoluble solid, known as a precipitate. In this scenario, the addition of Ba(NO3)2 leads to the formation of a white precipitate, indicating that a reaction has occurred. The identity of the precipitate can help identify the original solution based on the solubility rules of the involved compounds.

Solubility Rules

Solubility rules are guidelines that predict whether a compound will dissolve in water. For example, barium sulfate (BaSO4) is insoluble, while calcium chloride (CaCl2) and sodium chloride (NaCl) are soluble. Understanding these rules is crucial for determining which compounds will precipitate when mixed, aiding in the identification of the unknown solution.

Ionic Compounds and Their Reactions

Ionic compounds, such as AgNO3, CaCl2, and Al2(SO4)3, dissociate into their constituent ions in aqueous solution. The behavior of these ions during reactions, such as forming precipitates or remaining in solution, is essential for identifying the unknown solution. The lack of reaction with NaCl suggests that the solution does not contain ions that would form an insoluble compound with chloride ions.