Question

An aqueous solution of a cation (represented as blue spheres in the diagram) is allowed to mix with a solution of an anion (represented as green spheres) and the following result is obtained:

Which combinations of cation and anion, chosen from the following lists, are compatible with the observed results? Explain.
Cations: Na⁺, Ca²⁺, Ag⁺, Ni²⁺
Anions: Cl⁻, CO₂^3–, CrO₄^2–, NO₃^–

Accepted Answer

Step 1: Analyze the image provided. The diagram shows two solutions being mixed: one containing green spheres (representing anions) and the other containing red spheres (representing cations). After mixing, a solid precipitate forms at the bottom of the container, indicating that a chemical reaction has occurred and a precipitate has formed. Step 2: Understand the concept of solubility rules. Precipitation occurs when the product of a reaction between a cation and an anion is insoluble in water. Use solubility rules to determine which combinations of cations and anions can form an insoluble compound. Step 3: Evaluate the possible combinations of cations and anions provided in the problem. The cations are Na+, Ca2+, Ag+, and Ni2+, and the anions are Cl−, $$CO3^2$$−, $$CrO4^2$$−, and NO3−. Cross-reference these ions with solubility rules to identify which combinations produce an insoluble compound. Step 4: Apply solubility rules to each combination. For example, Ag+ often forms insoluble compounds with Cl− (AgCl is insoluble), while Na+ typically forms soluble compounds with all the anions listed. Similarly, Ca2+ can form insoluble compounds with $$CO3^2$$− (CaCO3 is insoluble). Continue this process for all combinations. Step 5: Based on the solubility rules and the observed precipitation in the diagram, identify the specific cation and anion pair that is compatible with the results. Ensure the pair corresponds to an insoluble compound forming a precipitate, as shown in the image.

비슷한 문제에 대한 검증된 영상 답변:

주요 개념

Ionic Compounds

Solubility Rules

Precipitation Reactions