A Critical Study on the Methods of Water Analysis (VI)

Silicate and Nitrite

Abstract

1. Silica'e: Diénert-Wandenbulcke's method has been studied. The presence of chloride up to about 20% Cl- causes no error where the tint becomes slightly yellowish, this is however easily Eeglected with a pale yellow glass filter. The small content of phosphate (0.1mg P₃O₅/l) and iron (1mg Fe/l) a so gives no influence for this analysis.
2. Nitrite: Griess-Romijin's powder reagent (α-naphtylamine lgr., sulphanilic acid 10gr. and tartaric acid 89 gr.) is especially well adapted to the analysis of the nitrite in water. NH₄C1, NaCl, KNO₃, Na₂CO₃, CaCl₂, Na₂NO₄, Na₂SiF₆, KH₂PO₄, MgCl₂ and small quantity of Fe⁺⁺⁺ and Fe⁺⁺ do not interfere with the analysis.