Equations Chromic chloride

Experiment 183. — Add to a few cubic centimeters of potassium dichromate solution a little concentrated hydrochloric acid and a few drops of alcohol. Warm gently. Two important changes occur. The chromate is reduced to chromic chloride which colors the solution green the alcohol is oxidized to aldehyde, which is detected by its peculiar odor. (See Exp. in ( ).) The equation is —... 

If 36.865 gm. of chromic chloride form 100 gm. of silver chloride, what is the atomic weight of chromium (Equation is 2 CrClg + 6 AgNOg = 2Cr(N03)3 + 6AgCl.)... 

N. Bjerrum found the results did not agree with the velocity equation for monomolecular reactions but the results were better represented by velocity equations for two consecutive, bimolecular reactions, on the assumption that the reaction involves the sequence of changes [Cr(H20)4Cl2]Cl->[Cr(H20)5Cl]Cl2 ->[Cr(H20)e]Cl3. If x, y, z respectively denote the concentrations of these three salts, then dxjdt=—kix, and dxldt=k. It was found that at 25°, A i=0-C0272 -J-O-0000162/s, and A 2=(3I/s+0-005/s2)10—7, where s denotes the cone, of free hydrochloric acid. For soln. with M mols of dark green chromic chloride, the... 

Miscellaneous Alkylations.—Chromic chloride is readily reduced by Li AIH4 to give a salt, presumably Cr", which can be used for the Grignard-type carbonyl addition to allyl halides [equation (18)]. Aldehydes are more reactive than ketones and can... 

Write equations for the reaction of a given alcohol with HCI, HBr, or HI, with cold, concentrated H2S04 or HN03, with PCI3 or PBr3, with thionyl chloride (SOCI2), or with an oxidant such as chromic anhydride or PCC. 

Coupling in para or ortho positions is easily accomplished with phenols 912,1037,1095] and aromatic amines [915]. -Naphthol, on refluxing with anhydrous ferric chloride in ether, is converted in 60% yield into a,a -bi-p-naphthol [9i2], and 2,4-bis(rert-butyl)-5-methylphenol, on heating with chromic acid, yields the corresponding dimer [1095] (equation 44). 

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