Photometric determination of nitrate. • Photometric determination with 2,6-dimethylphenol in sulphuric /phosphoric acid mixture. • In acidic solution nitrate ions react with 2,6-dimethylphenol to form 4-nitro-2,6-dimethylphenol, which can be evaluated photometrically • Determination of nitrate in accordance with ISO 7890-1. • Type: Tube test 0-65 • Range: 0,30 – 8,00 mg/l NO3-N; 1,3 - 35,0 mg/l NO3- • Sufficient for: 20 determinations • Sea water suitability: no