The determination of ammonia in sea water

A sensitive, specific and precise method for the determination of ammonia in sea water is presented. The method depends upon the oxidation of ammonia by chloramine-T and subsequent coupling with phenol to produce indophenol blue in an n -hexanol extract. Molar absorption coefficient ca 84,000. Values of ammonia measured in samples from the English Channel are given and the effect of freezing on samples for ammonia analysis is discussed.