On routine colorimetric determination of trace nitrates,by brucine,in the presence of chloride

A colorimetric method was developed for the determination of trace nitrates in solutions containing up to 50 g 1^?1 of sodium chloride. Beer's law applies, in such solutions for concentrations of up to 1 mg of NaNO₃ per liter. Effects of sodium chloride concentration and time on the development of color were quantitatively evaluated with an overall error of about 4%. Temperature effects on solutions analyzed were found to be a major cause of inconsistencies in this otherwise satisfactory method.