Answer to Question #219481 in Organic Chemistry for Gowtham

Question

How to prepare diphenylamine indicator stock solution

Answer 1

The usual preparation of diphenylamine indicator by shaking the amine with concentrated sulfuric acid is slow and time-consuming. If the amine is first melted to a clear liquid (m. p. m 52.9° C.) and the required amount of concentrated sulfuric acid then added, complete solution may be effected by 15 to 30 seconds' shaking.