Which of the following statements are not correct ?

A. Plaster of Paris is obtained on heating gypsum.

B. Sodium carbonate is an important constituent of baking powder.

C. Bleaching powder can also act as an oxidising agent.

D. Ten water molecules are present in one formulae unit of chemical species of a sample with common name blue vitriol.

E. Sodium hydroxide is produced by passing electricity through the aqueous solution of sodium chloride.