A-Text-Book-of-Pharmaceutical-Analysis-Practicals-ForB.Pharmacy-Students

Principle:

sulphuric acid is a strong acid, is standardized by titrating with a strong base i.e. sodium carbonate (primary standard). This is direct acid base titration in which sulphuric acid reacts with sodium carbonate to form carbon dioxide andwater. As carbon dioxide formed in reaction can change color of indicator before equivalence point it is advisable to boil solution to perform the errorless titration.

Na2CO3 + H2SO4                                   Na2SO4 + CO2 + H2O