POTASSIUM MERCURY- IODIDE SOLUTION, ALKALINE

METHOD OF PREPARATION: 

To 3.5 gm of potassium iodide, add 1.25 gm of mercuric chloride dissolved in 80 ml of water, add a cold saturated solutions of mercuric chloride in water, with constant stirring untill slight red ppts. Remain. Dissolve 12 gms of sodium hydroxide in the solution, add a little more of the cold saturated solutions. Of mercuric chloride and sufficient distilled water to produce 100 ml. Allow to stand and decant the clear supernatant liquid

[Store this solution at room temperature in Borosil glass bottles with well-fitted suitable stopper.]