Yes, a precipitate forms when lead(II) nitrate \((\text{Pb(NO}_3\text{)}_2)\) and potassium sulfate \((\text{K}_2\text{SO}_4)\) are mixed. The reaction can be represented as follows:
\[ \text{Pb(NO}_3\text{)}_2 (aq) + \text{K}_2\text{SO}_4 (aq) \rightarrow \text{PbSO}_4 (s) + 2\text{KNO}_3 (aq) \]
In this reaction, lead(II) sulfate \((\text{PbSO}_4)\) is formed as a solid precipitate. The empirical formula of lead(II) sulfate is \(\text{PbSO}_4\).