| 摘要 |
FIELD: chemistry. ^ SUBSTANCE: method involves converting iron (III) into a coloured complex compound in a sub acidic medium. 2 ml of acetate buffer solution with pH 4.7-5.7 is added to the iron solution as well as 0.7-1 ml of a solution of a surface active substance, containing 0.2% solution of polyoxyethylene monooleate sorbitan, 0.2% solution of monoalkylphenyl polyethylene glycol ester based on polymer distillate and water in ratio of 1:1:1, and 90-110-fold aluminon residue. Water is added to the obtained solution to 4 ml. The solution is then heated in a water bath at 80-98°C for 2-3 minutes and photometry is carried out at wave length of 364 nm. In an alternative to this method, 2 ml of acetate buffer solution with pH 4.3-4.8 is added to the iron (III) solution, as well as 0.1-0.2 ml of a solution of a surface active substance, containing 0.2% of a water solution of polyoxoethylene oxooctylphenyl ester, and 8-12-fold xylenol orange residue. Water is then added to the obtained solution to 10 ml. The solution is then heated in a water bath at 80-98°C for 2-3 minutes and photometry is carried out at wave length of 490 nm. ^ EFFECT: increased sensitivity and selectiveness of analysis. ^ 2 cl, 2 ex, 10 dwg |
