SCHEDULE 2 METHODS OF ANALYSIS

8b. DETERMINATION OF DIFFERENT FORMS OF NITROGEN IN THE SAME SAMPLE — IN THE ABSENCE OF CYANAMIDE NITROGEN

“8.1    VERIFICATION OF RESULTS

Before each analysis, check the functioning of the apparatus and the correct application of the methods used with a standard solution containing the different forms of nitrogen in proportions similar to those in the sample. This standard solution is prepared from solution of potassium nitrate (4.3), ammonium sulphate (4.4) and urea (4.5).