A Portable Apparatus for the Determination of Oxygen Dissolved in A Small Volume of Water

ABSTRACT In 1888 Winkler published his well-known method for the determination of oxygen dissolved in water. The principle of the method is as follows. A solution of manganous chloride is added to the water to be analysed, followed by a solution of sodium hydroxide containing potassium iodide. A precipitate of manganous hydroxide is first formed thus: