Final answer:
When aluminum is added to copper (II) chloride solution, a displacement reaction occurs where aluminum forms aluminum chloride and copper metal precipitates out, typically accompanied by a color change in the solution.
Step-by-step explanation:
When aluminum is added to a copper (II) chloride solution, a chemical reaction occurs. This chemical reaction is similar to when a copper wire is placed in a solution of silver nitrate as a demonstration of a spontaneous chemical change. In the case of silver nitrate and copper, the reaction involves the reduction of silver ions to elemental silver on the surface of the copper wire. Simultaneously, copper ions are released into the solution, which turns blue due to the presence of Cu2+ ions.
If we relate this to the aluminum and copper (II) chloride solution, we would expect that aluminum, being more reactive than copper, would displace the copper ions from the solution. This would lead to the formation of aluminum chloride, while copper metal would precipitate out. During this displacement reaction, the solution may change color similarly to the silver nitrate reaction, indicating the presence of different ions in solution.
Following the principles demonstrated in the previously mentioned reactions involving copper, we can infer that the observation in a reaction between aluminum and copper (II) chloride solution might include changes in color, the formation of a solid precipitate, and possibly the evolution of heat or other physical changes indicating a chemical reaction.