Chemical elements
    Physical Properties
    Chemical Properties
      Lead Tetramethyl
      Lead Tetraethyl
      Lead Tetraphenyl
      Lead Ethoxide
      Lead Fluoride
      Lead Tetrafluoride
      Hydrofluoplumbic Acid
      Lead Chloride
      Lead Chloride Double Salts
      Basic Lead Chlorides
      Lead Tetrachloride
      Ammonium Plumbichloride
      Lead Chlorite
      Lead Chlorate
      Lead Perchlorate
      Lead Dibromide
      Double Salts of Lead Bromide
      Basic Lead Bromides
      Lead Bromate
      Lead Iodide
      Lead Iodide Complex Salts
      Basic Lead Iodides
      Lead Tetra-iodide
      Lead Iodate
      Lead Periodates
      Lead Suboxide
      Lead Monoxide
      Lead Hydroxides
      Lead Dioxide
      Plumbic Acids
      Hexahydroxyplumbic Acid
      Colloidal Plumbic Acid
      Potassium Plumbate
      Lead Plumbate
      Calcium Orthoplumbate
      Lead Orthoplumbate
      Red Lead
      Metaplumbic Acid
      Calcium Metaplumbate
      Lead Metaplumbate
      Basic Lead Plumbate
      Lead Sulphide
      Lead Sulphohalides
      Lead Polysulphide
      Lead Sulphite
      Lead Sulphates
      Lead Sulphate
      Basic Lead Sulphates
      Lead Hydrogen Sulphate
      Plumbic Sulphate
      Lead Persulphate
      Lead Thiosulphate
      Lead Dithionate
      Lead Selenide
      Lead Selenite
      Lead Selenate
      Lead Telluride
      Lead Tellurite
      Lead Azide
      Lead Azoimide
      Lead Hydrazoate
      Lead Imide
      Lead Hyponitrite
      Lead Nitrites
      Lead Nitrate
      Lead saltpetre
      Basic Lead Nitrates
      Lead Hypophosphite
      Lead Phosphite
      Lead Orthophosphate
      Lead Monohydrogen Phosphate
      Lead Dihydrogen Phosphate
      Lead Pyrophosphate
      Lead Metaphosphate
      Lead Arsenite
      Lead Orthoarsenate
      Lead Hydrogen Arsenate
      Lead Pyroarsenate
      Lead Antimonate
      Lead Carbonate
      White Lead
      Lead Formate
      Lead Acetate
      Sugar of Lead
      Complex Lead Acetates
      Plumbic Acetate
      Lead Tetra-acetate
      Lead Oxalate
      Lead Tartrate
      Lead Silicates
      Lead Borates
      Normal Lead Chromate
      Lead Dichromate
      Basic Lead Chromate
      Lead Molybdate
      Lead Tungstate
      Lead Metatungstate
      Lead Diuranate
      Lead Peruranate
    PDB 1afv-3qjk

Lead Dichromate, PbCr2O7

Lead Dichromate, PbCr2O7, containing 2 molecules of water of crystallisation, was obtained by Preis and Rayman, but its existence was subsequently denied by Autenrieth. Elbs and Nubling found that when a very concentrated solution of chromic acid (130 grams CrO3 per 100 c.c.) is electrolysed with a lead anode a solution is obtained which evolves oxygen when kept, and deposits reddish brown needles of lead dichromate, PbCr2O7. From the volume of oxygen evolved it appears that plumbic dichromate is formed and decomposes thus:

Pb(Cr2O7)2 = PbCr2O7 + 2CrO3 + O.

Mayer obtained lead dichromate by heating lead acetate with chromic anhydride and concentrated nitric acid, under a reflux condenser; and Cox prepared the same salt by taking account of the fact that it is prone to hydrolysis and can only be formed in contact with a chromic acid solution of a certain concentration, which is 6.865 gram-molecules CrO3 per litre at 25° C. Thus by grinding together lead monoxide and chromium trioxide in saturated solution in the proportion of 2 gram-molecules of the former to 5 of the latter, lead dichromate is produced and may be obtained pure after washing with 7-N solution of CrO3. It is a lustrous, red, crystalline powder.

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