and wrought iron can be coated with copper by the new invention. The process consists in first removing the oxide from the iron to be coated, then covering it with a medium metal which has a great ...

Reduction is the gain of electrons by a substance. It is also the loss of oxygen from a substance. For example, copper(II) oxide can be reduced to form copper when it reacts with hydrogen: ...

The object of his experiment ... a piece of copper, so as to form a galvanic couple ; for zinc, when unconnected with a less oxidizable metalj is soon covered with a crust of oxide, so that ...