1. A colourimetric determination of oxime based on the oxidation with natriumhypoiodite in presence of sulfanilic acid to nitrite, and that of hydroxylamine in oxime solution based on the oxidation with iodine in presence of natriumacetate and sulfanilic acid to nitrite are described. 2. The effects of sulfaric acid on the oxime formation velocity of acetaldehyde, formaldehyde, benzaldehyde, and n-butylaldehyde were compared. The accelerative effect is specific to each oxime. 3. The effects of H2SO4 and NaOH on 10^-3 M acetaldoxime formation velocity were studied in detail. In presence of 0.85 N H2SO4 the maximum velocity, and of 0.5 N NaOH the minimum velocity were seen. And in proportion to the increase of NaOH greater acceleration was seen. In buffer solution on acidic side the maximum point was at pH 3.2, and on basic side the minimum point was at pH 9.2. In the case of 4 x10-5 M oxime the maximum point was at pH 4.4. From these results the maximum velocity is thought to be at the point of 〔NH2OH〕/〔H+〕=1/0.85.
Mendeley出力
