Starting with sodium chloride how would you proceed to prepare sodium peroxide ?

Explanation

Sodium chloride is first converted to sodium by electrolytic reduction. The metal is then heated in excess of air. The initially formed sodium oxide reacts with excess `O_2` to form `Na_2O_2`.
`4 Na + O_2 overset(Delta) to 2Na_2O , 2 Na_2 O + O_2 overset(Delta)to 2Na_2O_2`