摘要
保存二年以上的过二硫酸铵固体试剂，因逐渐分解而使溶液酸度过低，无法定量测出过二硫酸铵与碘化钾反应级数，改变各反应物量并加入适量氟化氢铵，可使反应顺利进行．
Solid ammonium persulphate remained over 2 years, its solution acidity was too low because of decomposition, reaction grade of ammoniuim persulphate and potassium iodide would not be determined quantitatively, After being changed the quantity of reactant and added ammonium hydrogenfluoride, reaction could carry on.
关键词
过二硫酸铵
氟化氢铵
化学反应速率
碘化钾
Ammonium Persulphate
Ammonium hydrogenfluoride
Sodium thiosulfati
Reaction rate
