Final answer:
The solubility of PbSO4 decreases with the addition of sulfuric acid, due to the common ion effect, which causes PbSO4 to precipitate by increasing the concentration of sulfate ions in the solution.
Step-by-step explanation:
The solubility of PbSO4 decreases with the addition of sulfuric acid due to the common ion effect. When sulfuric acid is added to a solution, it dissociates to produce more sulfate ions (SO42-), which is the same ion present in lead(II) sulfate. This increase in sulfate ion concentration shifts the solubility equilibrium to the left, causing PbSO4 to precipitate and thus decreasing its solubility.
Although adding other substances such as hydrochloric acid or sodium chloride might affect the solubility, they do so in different ways or to a lesser extent. For example, hydrochloric acid could increase the solubility of PbSO4 by forming a complex with lead ions, while sodium chloride increases the ionic strength of the solution but doesn't contain a common ion with PbSO4. Lastly, adding lead nitrate adds lead ions to the solution, which can increase the concentration of Pb2+ without affecting sulfate concentration directly, but according to Le Chatelier's principle, the increased Pb2+ would still lead to some precipitation of PbSO4.