The ionic formula of sodium chloride is NaCl. I'm not sure what is meant by "structural formula," but there is one chlorine for each sodium atom in the ionic compound.
The atomic ratio between sodium and chlorine in sodium chloride is 1:1, as indicated by its formula NaCl. If the mass ratio is wanted, it is that of the atomic weights of the two elements.
Sodium metal can be obtained by electrolysis from molten mixture of sodium chloride and calcium chloride in Down's cell. The metal can not be obtained by electrolysis from aqueous solution, because...