Getting precipitate of mercury(I) iodide

Bright orange precipitate

Scientific name: Reaction of Lead (II) Iodide and Mercury (I) Chloride


Double Displacement reaction of Lead (II) Iodide and Mercury (I) Chloride

by CSChemistry

Double Displacement Reaction of Lead (II) Iodide and Mercury (I) Chloride

by CSChemistry


Be careful with solutions of mercury and lead - they are very toxic! After the experiment, dispose the solutions of lead and mercury in a special way.

Always follow general safety recommendations. Please note that conducting chemistry experiments you must comply with the relevant legal procedures in your country.

Reaction formula

PbI2 + 2HgCl → 2HgI + PbCl2

Step-by-step instruction

WARNING! This experiment is dangerous! You should NOT perform this at home. ONLY carry out this experiment, if you are a trained chemist, and you understand local safety and legal requirements, which are required to perform such experiments

  1. You can use lead(II) iodide obtained in the experiment "Golden rain". Or you can get lead(II) iodide by mixing a potassium iodide solution and a lead nitrate solution.
  2. You have the precipitate of lead(II) iodide. Take a small amount of mercury(I) chloride and dissolve it in 10 ml of water.
  3. Add the solution of mercury(I) chloride to the lead(II) iodide.
  4. Shake the mixture.

Scientific background

Lead(II) iodide reacts with mercury(I) chloride and forms a bright orange precipitate of mercury(I) iodide.

PbI2 + 2HgCl → 2HgI + PbCl2


Published on 13 April 2015

  • Fire
  • Heating with fire
  • Explosion
  • Poisoned gas
  • Organic
  • Electricity
  • Solution
  • Oxidation reduction
  • Color change
  • Precipitate
  • Gassing
  • Catalyst