Question

Give the preparation of sulphuric acid in the earlier times.

Answer 1

In earlier times, sulphuric acid was prepared by heating green vitriol (ferrous sulphate heptahydrate, FeSO₄ . 7H₂O).

Due to its oily appearance and source, it was historically called the “Oil of Vitriol”.

Chemical Reaction:

\[\ce{2FeSO4 . 7H2O ->[\Delta] Fe2O3 + SO2 ^ + SO3 ^ + 14H2O}\]

The SO₃ gas dissolves in water vapour to form sulphuric acid.