(NH_4)_2S_2O_8和KI反应级数测定实验的改进

Improvement of Experimental Reaction Order Testing on (NH_4)_2S_2O_8 and KI

对(NH4)2S2O8和KI反应级数测定的失败原因进行了分析,主要为长期存放的(NH4)2S2O8试剂部分变质,可以通过添加适量的Na2SO3,除去过硫酸铵(NH4)2S2O8分解产生的活性氧化物质,处理后的(NH4)2S2O8溶液用于反应级数测定实验,可以获得反应物浓度与反应速率的良好线性关系,同时优化了本实验测速剂Na2S2O3在不同室温下的"842"比例方案,改善了实验教学效果。

This paper mainly deal with the failure reasons for the reaction order testing of （NH4）2S2O8 and KI, which is mainly because long-term storage of （NH4）2S2O8 makes the reagent partly deteriorated. The deterioration by adding the right amount of Na2SO3 can remove reactive oxygen species of decomposed production of ammonium per sulfate. Using the treated solution of （NH4）2S2O8 for the reaction order testing experiments can obtain good linear relationship between the concentration of reactants and reaction rate, meanwhile it optimizes the ＂842＂ scale program of the speed testing agent under different room temperatures and improves the experiment teaching effect.