How is oxalic acid manufactured from sodium formate ?

The main process for the manufacture of sodium carbonate is :

How is ammonia manufactured by Haber's process?

How is phenol manufactured by Cumene process?

How are carboxylic acid prepared from Grigoard reagent?

How is Methane prepared from sodium acetate?

(i) "Sodium is a highly reactive metal and it cannot be obtained from its oxide by heating with carbon". Give reason. (ii) How can sodium be obtained from sodium chloride ?

How is potassium permanganate manufactured from "MnO"_(2) ?

How is potassium permanganate manufactured from MnO_(2) (pyrolusite)?