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Home › Miscellaneous Chemicals › Iodide of Lead
Iodide of Lead
Acetate of lead, 9 ounces; water, 6 pints; dissolve; iodide of potassium (pure), 7 ounces; water, 2 pints; dissolve. Add the latter solution to the former, With caustic potassa they give a light blue wash and dry the precipitate, and keep it from bulky precipitate, turning blackish-brown or black on boiling the liquid.
Ammonia and carbonate of ammonia produce a bluish-white precipitate, soluble in excess of ammonia, yielding a rich deep blue solution.
The carbonates of potassa give a similar precipitate to the last, but insoluble in excess of the precipitate.
Ferrocyanide of potassium gives a reddishbrown precipitate. Sulphuretted hydrogen and hydrosulphuret of ammonia give a blackish-brown or black one. the light. Or: Iodide of potassium and nitate of lead, of each 1 ounce; dissolve each separately in 1/4 pint of water, mix, collect the precipitate in a muslin or linen filter, and wash it with water; then boil it in 3 gallons water, soured with pyroligneous (acetic) acid, 3 fluid ounces; let the solution settle (still keeping the liquid near the boiling point), and decant the clear; as the water cools, the iodide will subside in brilliant golden yellow lamellæ, or minute crystals.
The latter is the best process, as any adhering oxide of lead is dissolved out by the A polished rod of iron, on inmersion in an acid. (Cooley). acidulated solution, quickly becomes coated 4104. Chromate of Lead. To a filwith metallic copper. 4100. Delicate Test for Iron and Copper. The alcohol tincture of logwood will produce a blue or bluish-black tint in water which has been run through iron or copper pipes, when neither tincture of galls, sulphocyanide, nor the ferrid and ferrocyanides of potassium show any reaction. tered solution of acetate or nitrate of lead, add a filtered solution of chromate of potassa, as long as a precipitate forms, which is collected, washed with water, and dried. This forms chrome-yellow. (See No. 2705.)