葡萄糖-BrO3--Mn2+-H2SO4-丙酮体系的振荡反应

Oscillating Reaction of the Glucose -BrO3--Mn2+-H2SO4-Acetone System

关键词:  葡萄糖-BrO₃^--Mn²⁺-H₂SO₄-丙酮体系  振荡反应

Key words:  Glucose-BrO₃^--Mn²⁺-H₂SO₄-Acetone System  oscillating reaction

摘要:

以葡萄糖为有机底物,与-BrO₃^--Mn²⁺-H₂SO₄-丙酮组成振荡反应体系,在恒温条件下进行振荡反应。结果表明:反应有诱导期,体系电导(L)不随时间(t)变化;振荡周期,L随t发生周期变化,溶液颜色在粉红色与无色之间交替变化,有典型的振荡波型。诱导期及振荡周期反应的表观活化能分别为84.275kJ/mol和98.153kJ/mol。体系振荡反应物浓度范围[葡萄糖]0.01~0.02mol/L,[BrO₃^-]0.03~0.045mol/L,[Mn²⁺]0.06~0.08mol/L,[丙酮]0.27~0.30mol/L,[H₂SO₄]0.8~1.2mol/L。振荡反应有Br₂产生,Br₂准一级消耗速率常数k_Br2=1.6×10^-5S^-。对温度、反应物浓度、丙酮、Mn²⁺、Cl^-、底物对振荡反应的影响作了探讨。

Abstract:

Oscillating reaction system is composed of BrO₃^--Mn²⁺-H₂SO₄-Acetone and glucose. The reaction has conducted under the constant temperature. The results show that the reaction has induced stage, at which electro-conductivity (L) is unchanged along with time (t),and Oscillating stage, at which electro-conductivity periodically changes along with time, salution colour changes between pink and uncoloured afternately,The oscillating wave type is typical. The apparent activation energy of the reaction at reduced sarge is 84.275 kJ/mol, and 98.153 kJ/mol at oscillating stage. The concentration ranges of the reactants are:[Glucose]0.01~0.02 mol/L,[BrO₃^-]0.03~0.045 mol/L,[Mn²⁺] 0.06~0.08 mol/L,[Acetone] 0.27~0.30 mol/L,[H₂SO₄] 0.8~1.2 mol/L. Br₂ is produced in the reaction. The quasi first consumption rate constant k_Br2=1.6×10^-5S^-. The effects of temperature、reactant concentration、Acetone、Mn²⁺、Cl^-、substrate on oscillating reaction are also discussed.