Mercuric dichromate

Mercuric Dichromate, HgCrjO, is obtained as a light orange powder from a solution of the chromate in chromic acid, the concentration of the solution at 25° C. being greater than 10-4-6 gram-molecules of chromic acid per litre. It forms deep carmine-red crystals. 

Atropine causes dilation of the pupil of the eye. A drop or two of an aqueous solution, containing 1 part in 130,000 parts of water, introduced into the eye of a cat is sufficient to produce this effect. When warmed with sulphuric acid and a small crystal of potassium dichromate, atropine develops a bitter almond odour. Evaporated to dryness on a water-bath with concentrated nitric acid, it gives a residue which becomes violet on adding a drop of sodium hydroxide solution in alcohol (Vitali s test). With a solution of mercuric chloride atropine gives a yellow to red precipitate of mercuric oxide. 

Those epimers of 1,2,3,4-tetrahydro-j8-carbolines of general structure 139, in which the hydrogen on carbon-1 of the carboline moiety is axial, are converted into the corresponding 3,4-dihydro- -carbolinium salts (141) by mercuric acetate oxidation. Sodium dichromate... 

The oxidation of tetrahydro-j8-carboline to dihydro-jS-carbolinium salts (341-> 342 342a->343) by -butyl hypochlorite (X = Cl), dichromate, or mercuric acetate (cf. Section III,C, 2,b), followed, by treatment with acid, and to j8-carbolinium salts (341 ->344) by lead tetraacetate [X = Pb(OAc)3] (cf. Section III, E, 2, a, ii) in acid solution... 

Chromium compounds interact synergistically or antagonistically with many chemicals. For example, potassium dichromate administered by subcutaneous injection potentiated the effects of mercuric chloride, citrinin, and hexachloro-1,3-butadiene on rat kidneys (USPHS 1993). Chromium effects were lessened by ascorbic acid and Vitamin E, and N-acetyl cysteine was effective in increasing urinary excretion of chromium in rats (USPHS 1993)... 

Baggett, J.M. and Bemdt, W.O. (1984). Interaction of potassium dichromate with the nephrotoxins, mercuric chloride and citrinin. Toxicology 33(2) 157-169. 

Ruegg, C.E., Gandolfi, A.J., Nagle, R.B. and Brendel, K. (1987b). Differential patterns of injury to the proximal tuhule of renal cortical slices following in vitro exposure to mercuric chloride, potassium dichromate or hypoxic conditions. Toxicol. Appl. Pharmacol. 90 261-273. 

Mercuric oxide (5 g.) is dissolved for the most part in a still warm mixture of 110 c.c. of water and 50 c.c. of concentrated sulphuric acid. The mixture is brought into a large hydrogenation flask (Fig. 58, p. 377) and shaken for some time with acetylene prepared from calcium carbide, purified with acid solutions of dichromate and copper nitrate, and collected over saturated sodium chloride solution in a glass gas-holder (capacity 10-15 litres). Before shaking is begun the air present must be displaced by the hydrocarbon. 

Diazirines have been prepared by dehydrogenation of diaziri-dines with mercuric oxide, silver oxide, or dichromate-sulfuric acid. The present procedure corresponds to that of Schmitz and Ohme. The procedure for the preparation of the 3,3-penta-methylenediaziridine has been reported by H. J. Abendroth. ... 

Source Manufactured by oxidizing ethanol with sodium dichromate and sulfuric acid or from acetylene, dilute sulfuric acid, and mercuric oxide catalyst. 

Potassium Chlorate. .. Potassium Triiodo Mercurate(ll) Potassium Chloride Potassium Chlorate Potassium Chromate Potassium Cyanide Potassium Dichromate Potassium Ferricyanide Potassium Ferrocyanide Potassium Fluoride Potassium Formate Potassium Hydride Potassium Hydrogen Phthalate Potassium Hydroxide Potassium lodate... 

Hydrogen trisulphide is much more easily combustible than the crude parent hydrogen polysulphide. Exposure to light tends to accelerate its decomposition. It slowly reduces concentrated sulphuric acid to sulphur dioxide, whilst on contact with dry silver oxide, cupric oxide, lead dioxide or mercuric oxide, it bursts into explosive combustion,2 a residue of the metallic sulphide being obtained. Many other metallic oxides and most salts bring about a less vigorous decomposition metals in the massive condition only react with it slowly. With potassium permanganate or dichromate the reaction is violent. 

If sampling is not followed immediately by analysis, the sample must be treated with a preservative, but not such as to falsify the analytical results use is made of 10% potassium dichromate solution, formaldehyde, hydrogen peroxide, alcoholic solution of phenol, mercuric chloride (about 5% solution), etc., a few drops being added. The last of these preserves milk very well for several days without altering its composition or disturbing the determinations, but its poisonous character necessitates precautions. 

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