Mercuric Chloride Potassium Iodide

No turbidity with alkaline mercuric chloride—potassium iodide reagent USP test. 

Dobbin s reagent analychem A mercuric chloride-potassium iodide reagent used to test for caustic alkalies in soap. dab-anz re a- ant ... 

From the terminal alkyne and K2Hgl4 (prepared from mercuric chloride, potassium iodide.ana potassium hydroxide)... 

Materials Zinc, copper, solutions of copper sulphate, sodium chloride, mercuric chloride, potassium bromide, potassium iodide, iodine, bromine water, chlorine water, carbon disulphide. 

About every other year from 1900 onward there was a question about the work of one or two eighteenth- or nineteenth-century chemists such as Cavendish, Lavoisier, Dalton, Davy, and Faraday. Other historical questions included Describe, and explain, the principle of the spectroscope. How has this led to the discovery of new elements and to a knowledge of the sun and stars , which links astronomy with the discovery of the periodic system. Another question, from 1918, was, In what respect has the discovery of radioactivity modified our conception of the chemical atom There were, however, only a few historical/philosophical questions, with most questions being more factual, such as, How does ammonia react with chlorine, mercuric chloride, potassium, ethyl iodide, ethyl oxalate ... 

Acetamido-4-methylselenazole can react with mercuric acetate to yield 5-mercuriacetate derivatives that can be converted to the chloro derivatives by the action of sodium chloride. Treatment with potassium iodide leads to reduction regenerating the initial compound with loss of mercury (Scheme 16) (4). 

Nicotine may be detected by the colourless, crystalline mercurichloride obtained when an aqueous solution is added to a solution of mercuric chloride, by the black precipitate formed under similar conditions with potassium platinic iodide and the characteristic crystalline periodide, BI2. HI, m.p. 123°, produced on admixture, under specified conditions, 2 of ethereal solutions of nicotine and iodine (cf Anabasine, p. 43). A polarographic study of nicotine has been made by Kirkpatrick. ... 

Determination of the Iodine Value.—Pure iodine (2-5 g.) and mercuric chloride (3 g.) are each dissolved in 50 c.c. of pure spirit and the clear solutions are mixed. After twelve hours the iodine titre of the mixture is determined in a 10 c.c. portion by adding 10 c.c. of 10 per cent potassium iodide solution and titrating with 0-1 IV-thiosulphate solution. 

Most alkaloids are isolated from plant extracts by conversion into the difficultly soluble salts which they form with complex acids such as hexachloroplatinic acid, chlorauric add, phosphotungstic add, hydroferro-cyanic add, Rdnecke s add, etc. Perchloric add, picric add, flavianic add, mercuric chloride, iodine in potassium iodide are also used. 

Many derivatives of this series of salts have been prepared. For example, the chloride, if freshly prepared, yields in aqueous solution crystalline salts with chloroplatinic aeid, potassium iodide, and mercuric chloride,1 and numerous acido-derivatives have been prepared. 

Additional Exercises Calcium hydroxide from sodium hydroxide and calcium chloride silver nitrite from silver nitrate and sodium nitrite manganese sulfite, MnSChSHsO, from manganese chloride and sodium sulfite (adding a little S02 to the solution) mercuric iodide from potassium iodide and mercuric chloride. 

Arsenic triiodide also dissolves, the saturated solution at 15° C. having density 3-661. Other soluble halides are potassium bromide, anhydrous ferric and aluminium chlorides 6 and tetramethyl ammonium iodide but the iodides of rubidium, cadmium, manganese and cobalt, also mercuric and stannic iodides, and cobalt and stannic bromides, are insoluble or only very slightly soluble in arsenic tribromide. The liquid also dissolves phosphoryl bromide and, very slightly, ammonium thiocyanate. In the mixed solutions of halides, the components may react chemically (cf. p. 106), but such is not always the case for example, with antimony tribromide a continuous series of solid solutions is formed.7... 

A solution of 13.5g of mercuric chloride in 150ml of water is mixed with one of 16.6g of potassium iodide in 200ml of water. The red mercuric iodide is suction-filtered, washed well with 100ml of water, and dried in a desiccator. 

A solution of 13,5g of mercuric chloride in 200ml of water is mixed with 16.% of potassium Iodide In 160ml of water and the red precipitate of mercuric iodide is filtered off, washed with two 25ml portions of water, and drained diy, It is then dissolved in a hot solution of 16g more of potassium iodide in 10ml of water, the yellow supernatant liquid is decanted from the small residue of undissolved mercuric iodide, and allowed to crystallize in vaciw over concentrated sulphuric add, The crystalline crusts on the surface should be broken up from time to time. The final paste of light-yellow crystals is completely dried in an ordinary desiccator. Based on the mercuric chloride taken, the yield is almost quantitative. The product is deliquescent and should be stored in tightly stoppered vessels to avoid absorption of moisture from the air. 

Mercuric iodide is precipitated by mixing solutions containing 6.8g of mercuric chloride and 8.3g of potassium iodide. The washed material is dissolved in 50ml of water containing a similar quantity of potassium iodide, and mixed with a saturated aqueous solution of 12g of copper sulfate 5-hydrate. A stream of sulfur dioxide is passed into the mixture until precipitation is complete and the supernatant liquid is very faintly colored. 

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