Mercury oxide, red

HFCO[g] CARBON OXIDE-HYDRIDE-FLUORIDE (GAS) 791 HgO MERCURY OXIDE (RED) 830... 

Synonyms Cl 77760 Mercuric oxide (INCI) Mercuric oxide, red Mercury oxide Mercury (II) oxide Mercury oxide, red Red precipitate Classification Inorganic oxide Empirical HgO... 

Mercury oxide, red. See Mercury oxide (ic), red Mercury oxide, yeiiow. See Mercury oxide (ic), yellow... 

Although red mercuric oxide usually vigorously decomposes hydrogen peroxide, the presence of traces of nitric acid inhibits decomposition and promotes formation of red mercury(II) peroxide. This explodes on impact or friction, even when wet, if the mercury oxide was finely divided. 

Mixtures of the alloy with silver oxide or mercury oxide are shock-sensitive powerful explosives. The red form of mercury(I) oxide gives mixtures 40 times, and the yellow form 140 times as sensitive as mercury fulminate. 

Red phosphorus reacts vigorously on heating with copper oxide or manganese dioxide and on grinding with lead oxide, mercury oxide or silver oxide, ignition may occur. Red phosphorus ignites in contact with lead peroxide, potassium peroxide or sodium peroxide, while white phosphorus explodes, and also in contact with molten chromium trioxide at 200°C. 

Mercury oxide (HgO) exists in two forms, red and yellow mercuric oxides, and is related to mercurous oxide (Hg O), which is black. All have industrial uses, ranging from antiseptics to pigments. 

Accdg to Davis (Ref 2), Fourcroy, by digesting red oxide of mercury (HgO) in ammonia water for 8 to 10 days, prepd a material which became white and finally assumed the form of crystalline scales. The dried product exploded loudly from fire, but underwent spontaneous de-compn when left alone. At slightly elevated temp it gave off ammonia and left a residue of mercury oxide... 

Treatment 2,3-dichloro-5-(trichloromethyl)pyridine in anhydrous hydrogen fluoride with mercury(II) oxide (red) at room temperature for 22 hours provides 2,3-dichloro-5-(tri-fluoromethyl)pyridine in 98% yield.59... 

Nitroso azoxybenzene, ON C6H -N (0 )N CeHsmw 227.22, N 18.49% sulfu yel crysts, mp ca 106° with a blue-green color becoming om-red. It was prepd by heating on a steam bath 2-hydroxyI-amino-azoxybenzene with freshly pptd mercury oxide in ether... 

It is stated that protoxide of mercury ia occasionally adulterated -with minium or red lead, sesquioxide of iron, and powdered brick. Such substances are readily detected by heating the substance to a dull heat the protoxide of meroury sublimes, and leaves the nonvolatile matters in the crucible, or the mercurial compound maybe treated with dilute nitric add, to dissolve the mercurial oxide and should minium be present, a pace-colored binoxide of lead remains together with the other adulterants, if any be present. On adding dilute sulphuric acid to the door liquor obtained in the foregoing, a white precipitate of sulphate of lead falls, corroborative of the existence of a lead compound. 

There are mercury compounds with mercury oxidation numbers lower than +1, e.g. +0.5,16,21 +0.6713,15,27 or +0.35.18,20 Yellow crystals of Hg3(AsF6)2 have been formed by the reaction of metallic mercury with AsFs in liquid S02.13 X-Ray structure determination showed a linear polycation Hg+—Hg—Hg+ with Hg—Hg distances of 255 pm.15 Metallic mercury and SbF5 react in liquid S02 to form Hg3(Sb2Fu)2.15,23 The Hg—Hg distances in the complex Hg3(AlCU)2 are 256 pm 14 the Hg—Cl distances are 251 and 256 pm the Hg—Hg—Hg angle is 174°. Dark red crystals of Hg4(AsF6)2 were obtained in liquid S02. This coordination compound contains centrosymmetric Hg4+ ions, which are connected to chains (see l).21... 

Metal Oxides. Red phosphorus reacts vigorously on heating with copper oxide or manganese dioxide. It may ignite on grinding or warming with lead monoxide or mercury or silver oxides. It ignites in contact with lead, sodium, or potassium peroxides. White phosphorus explodes in contact with the latter peroxides.18... 

Mercury compounds (mercuric oxide, red mercuric oxide, yellow mercurous chloride mercury bichloride)... 

---