| abstract |
The invention relates to a method for the determination of phosphate in a water sample, said method comprising the steps of: b) taking a sample of water; c) adding an acid so that the concentration of the acid in the water sample equal to at least 0.5% by weight, d) perform a first photometric measurement of the water sample solution, e) add a dye to the photometric water sample solution, f) perform a second photometric measurement and g) calculate the phosphate concentration from the difference between the first and the second photometric measurement. |