(1) 50 g iodine dissolved in 1 L of 95% alcohol; (2) 60 g mercuric chloride dissolved in one L of alcohol; (3) Make up an iodine monochloride solution from (1) and (2). Add an excess to a known weight of the fat or oil dissolved in chloroform. The excess of iodine chloride can be estimated by the potassium iodide and thiosulfate method. By running a blank test, the amount of iodide absorbed can be estimated.