the amount of electric current passing through a cross-sectional area (perpendicular to the direction of current) of a conductor in a given unit of time: commonly expressed in amperes per square centimeter or amperes per square inch
Such an irregular distribution of the bath, with strong copper sulphate solution from the anode at the bottom and acid solution from the cathode at the top, not only alters the conductivity in different strata and so causes irregular current-distribution, but may lead to the current-density in the upper layers being too great for the proportion of copper there present.
The chief differences between the commercial systems of refining lie in the arrangement of the baths, in the disposition and manner of supporting the electrodes in each, in the method of circulating the solution, and in the current-density employed.
A high current-density being employed, the turn-over of gold is rapid - an essential factor of success when the costliness of the metal is taken into account.
The relation between the composition of the electrolyte and the various conditions of current-density, temperature and the like has been studied by F.
With high current-density, heating the solution tended to increase the proportion of chlorate to hypochlorite, but as the proportion of water decomposed is then higher, the amount of chlorine produced must be less and the total chlorine efficiency lower.