When aqueous sodium hydroxide (NaOH) is added to a solution of copper(II) chloride (CuCl₂), a chemical reaction occurs resulting in the formation of a precipitate. Copper(II) chloride in solution is typically a blue solution due to the presence of Cu²⁺ ions.
Upon the addition of sodium hydroxide, a blue precipitate of copper(II) hydroxide (Cu(OH)₂) forms. This precipitate appears as a light blue solid. The overall reaction can be summarized as follows:
\[ \text{CuCl}_2 (aq) + 2 \text{NaOH} (aq) \rightarrow \text{Cu(OH)}_2 (s) + 2 \text{NaCl} (aq) \]
In summary, when you add aqueous sodium hydroxide to copper(II) chloride, you will observe the formation of a light blue precipitate of copper(II) hydroxide.