Illustration of a precipitation reaction in inorganic chemistry: a colorless solution of potassium iodide is added to colorless solution of lead nitrate, with the formation of an insoluble precipitate of lead iodide (which will appear as a cloudy yellow suspension). Equation: Potassium iodide (aqueous) + Lead Nitrate (aqueous) Lead iodide (precipitate) + Potassium Nitrate (aqueous).