A method for the determination of micro amounts of iodine in milk powder by the derivable gas chromatography has been developed.The protein in the sample was removed using the zinc acetate and the potassium ferrocyanide as the precipitating agent and the fat in the sample was removed by cyclohexane counter extract.The iodine ion was oxidized into free iodine with the potassium dichromate under the sulfuric acid environment,and into free iodine reacts on 2-butanone produce iodobutanone(3-iodine-2-butanone) t...