Division 6.4.2

Add, from the burette, the observed titre of the sample solution (as determined in 63) less 1 ml. Add some anti-bumping granules, mix the contents of the flask by swirling, boil the flask and contents and titrate as previously (6.3). The end-point should be reached one minute from the time of addition of the methylene blue solution. Final titre = V₁.