In "cold galvanizing" the zinc is deposited electrolytically from a bath, preferably kept neutral or slightly acid, containing a io% solution of crystallized zinc sulphate, ZnSO 4.7H20.
In 1826 he described the prismatically-coloured films of metal, known as Nobili's' rings, deposited electrolytically from solutions of lead and other salts when the anode is a polished iron plate and the cathode is a fine wire placed vertically above it.
A continuous electric current of one ampere is defined to be one which deposits electrolytically 0.001118 of a gramme of silver per second from a neutral solution of silver nitrate.'
In quantitative analysis the methods can be subdivided into: (a) gravimetric, in which the constituent is precipitated either as a definite insoluble compound by the addition of certain reagents, or electrolytically, by the passage of an electric current; (b) volumetric, in which the volume of a reagent of a known strength which produces a certain definite reaction is measured; (c) colorimetric, in which the solution has a particular tint, which can be compared with solutions of known strengths.
We may take it, then, that only that portion of these bodies is chemically active which is electrolytically active - that ionization is necessary for such chemical activity as we are dealing with here, just as it is necessary for electrolytic conductivity.
In 1852 magnesium was isolated electrolytically by R.
Hydrogen and oxygen may also be produced electrolytically as gases, and their respective reducing and oxidizing powers at the moment of deposition on the electrode are frequently used in the laboratory, and to some extent industrially, chiefly in the field of organic chemistry.
Electrolytically, generally applied to the solutions obtained in processes (3) and (4).
Then, by the use of another piece of platinum as anode, mercury is electrolytically deposited upon the platinum, which may also be amalgamated by making it white hot in a Bunsen flame and plunging it in mercury.
In practice, however, it cannot be thrown down electrolytically with a dissimilar anode so as to win the metal, and certain difficulties are still met with in the analogous operation of plating by means of a similar anode.
About 7 o% of the world's annual copper output is refined electrolytically, and from the 461,583 tons refined in the United States in 1907, there were recovered 13,995,436 oz.
The anode residue is collected in the angular bottom of the tank, the electrolyte passes from the anode chamber to a series of tanks in which the more electro-negative constituents (silver, &c.) are chemically separated, and thence to the cathode chamber, where the copper is deposited electrolytically, thence it passes again to the anode chamber and so completes the cycle.
Platinized platinum (platinum foil upon which a thin film of platinum had been deposited electrolytically) and charcoal were rendered incandescent, black paper and matches immediately inflamed, ordinary brown paper pierced and burned, while thin white blotting-paper, owing to its transparency to the invisible rays, was scarcely tinged.
It may be obtained electrolytically from solutions of ferrous and magnesium sulphates and sodium bicarbonate, a wrought iron anode and a rotating cathode of copper, thinly silvered and iodized, being employed (S.