Rapid Kinetic Experiments for the Advanced Chemistry Laboratories

动力学实验常常受到手工混合的限制，因为手工混合会产生非典型的缓慢反应。这些反应并不代表现实世界中遇到的情况。这一限制正在通过购买带有荧光和吸光度检测设备的止流装置来解决。正在开发六个动力学实验，说明基本的化学和生物过程，并将它们纳入物理、分析、无机和生物化学实验室。这些新的实验正在培养学生的化学直觉，让他们对反应发生的时间尺度有一种感觉。例子包括非常快的质子转移反应和蛋白质折叠的慢得多的速率。正在进行的实验有：基于CO2 -碳酸-碳酸氢盐平衡的质子转移实验；Fe(CN)64-对钴（III）五胺配合物的还原，证明了离子对形成和电子转移的离散性；配体置换两个实验，一个显示比预期的八面体置换速率更快，另一个作为经典分光光度多组分分析的替代方法，使用时间而不是波长作为鉴别器；蛋白质折叠：用荧光探针作为构象变化的标记物，测定几种蛋白质的再折叠率，以分离该过程的各个阶段；酶动力学chance方法应用于过氧化物酶，证明了酶底物复合物的形成及其与产物形成同时消失。该仪器对实验室课程产生了重大影响，因为它使教师能够让学生更好地了解基本的化学过程和动力学，同时让他们接触到最先进的仪器。＊

Kinetic experiments are often limited by the necessity of hand mixing, which produces atypically slow reactions. These reactions are not representative of those encountered in real-world situations. This limitation is being addressed by the purchase of a stopped-flow apparatus with fluorescence and absorbance detection equipment. Six kinetic experiments are being developed that illustrate fundamental chemical and biological processes and incorporate them into the physical, analytical, inorganic, and biological chemistry laboratories. These new experiments are developing the chemical intuition of the students, giving them a sense of the time scales over which reactions occur. Examples include the very fast proton transfer reactions and the much slower rates involved in protein folding. The experiments being developed are: Proton Transfer an experiment based on the CO2 carbonic acid bicarbonate equilibrium; Electron Transfer the reduction of cobalt (III) pentamine complexes by Fe(CN)64-, which demonstrates the discrete nature of ion pair formation followed by electron transfer; Ligand Substitution two proposed experiments, one that shows faster than expected rates for octahedral substitution, and the other that serves as an alternative to classic spectrophotometric multicomponent analysis by using time rather than wavelength as the discriminator; Protein Folding the determination of the rates of refolding of several proteins separating the various stages of the process by using a fluorescent probe as a marker for conformational changes; and Enzyme Kinetics chance's method applied to peroxidase, which demonstrates the formation of the enzyme substrate complex and its concurrent disappearance with the formation of product. The instrument is having a significant impact on the laboratory curriculum because it allows teachers to give students a better sense of fundamental chemical processes and kinetics while exposing them to state-of-the-art instrumentation. *