1.1 This method describes the test for the determination of acidic or alkaline constituents in petroleum products and lubricants. This method splits these constituents into groups having, depending on their ionization, weak acid, strong acid, weak base and strong base properties, provided that the dis ociation constant of the strong acid or strong base compounds is at least to ooo times higher than that of the next weak group. I.'1 There is a titration method n oolorant indicator (N1)H W.oUiJ). The neutralization indices obtained by the potentiomotric method give figures which are not necessarily identical 6. those obtained by the method a coloring indicator.