Video: Reaction of lead(II) ion with iodide ion
A characteristic test for lead(II) ion is the production of bright yellow lead(II) iodide:Pb2+(aq) + 2 I-(aq) ® PbI2(s)
Addition of excess iodide ion results in the formation of the colorless soluble tetraiodoplumbate(II) complex ion.
PbI2(s) + 2 I-(aq) ? [PbI4]2-(aq)