Question

Give briefly the isolation of magnesium from sea water by the Dow's process. 

Give equations for the steps involved.

Answer 1

In sea water MgCl₂is also present which can be precipitated as Mg(OH)₂ by addition of lime water.

This MgCl₂ in fused state is mixed with fuse KCI and then this fuse mixture is electrolysed in Fe crucible (which acts . as cathode and graphite rod is used as anode).

The electrodes are separated by a porous diaphragm and electrolysis is carried out in an atmosphere of coal gas (inert atmosphere).