The following Notes have been saved in Adobe PDF format. You must have Adobe Acrobat Reader installed in order to read these Notess - if you don't have Acrobat Reader installed, follow the link to the Adobe website to safely install this useful software.   ALKALINITY - Bp Blue method   Alkalinity is determined by measuring the absorbance spectrophotometrically at 600nm of the complex formed when a sample is reacted with bromophenol blue in a phthalate buffer at pH 3.5,.   Click here to read this Note     ALKALINITY - Methyl Orange method (EPA 310.2)   Methyl orange is used as the indicator because its pH range is the same as the equivalence point for total alkalinity. The Methyl orange is dissolved in a weak buffer (pH 3.1) just below the equivalence point. The loss of colour is directly proportional to the concentration of alkalinity and is measured at 540 nm   Click here to read this Note     AMMONIA - Phenolate (EPA 350.1)   Alkaline phenol and hypochlorite react with ammonia to form indophenol blue that is proportional to the ammonia concentration. The blue colour is intensified with sodium nirotprusside   Click here to read this Note     Ammonia DIC   Ammonia reacts with hypochlorite ions generated by the alkaline hydrolysis of sodium dichloroisocyanurate to form monochloramine. This reacts with salicylate ions in the presence of sodium nitroprusside at around pH 12.6 to form a blue compound. The absorbance of this compound is measured spectrophotometrically at wavelength 660nm and is related to the ammonia concentration by means of a calibration curve   This is a password protected Application Note, Click here to read this Note     BORON   Azomethine – H is reacted with the sample to form a coloured complex which is measured spectrophotometrically at wavelength 405nm   Click here to read this Note     BROMIDE (SMWW 4500 Br - D)   Bromide is oxidised to bromine by Chloramine-T followed by substitution of bromide on phenol red to produce bromo phenol blue. The absorbance measured at 600nm is proportional to the concentration of bromide in the sample. Sodium Thiosulphate is added to reduce interference from chloride   Click here to read this Note   Search Results: Notes 1 to 6, of 36 items found