The solution on acidification yields a yellow precipitate of this sulphide.
The product on acidification gives a compound C15H1205 ï¿½ H20 which is probably an oxy-methoxy-benzoyl benzoic acid.
Baeyer in 1890, by heating alizarin with fuming sulphuric acid for 24-48 hours at 35-40° C., obtained a product, which after treatment with caustic soda gave a sulphuric acid ester of quinalizarin, and this after acidification and boiling was converted into quinalizarin (Alizarin Bordeaux) or 188.8.131.52 tetra-oxyanthraquinone.
Oc 2 H 5 H Chï¿½C]](ONa) :CHï¿½000C2H5; and on acidification this last substance gives aceto-acetic ester.
Acidified copper nitrate solution is run into this cell, copper is deposited, and the more or less spent solution then passes through the linen partition, and, taking up metal from the anodes by electrolytic solution, is run out of the trough through a series of vessels filled with copper by which the silver is precipitated by simple exchange; after acidification the resulting silver-free copper solution is returned to the cathode cell for the deposition of the copper, the solution being employed again and again until too impure for use.