The popular elephant’s toothpaste demonstration can be used to demonstrate the effect of temperature on reaction rate qualitatively. Our version is designed for simplicity of execution and to require little class time. Two runs of the reaction are performed at easily achieved temperatures (ice and ambient), the latter being approximately three times as fast. The reaction behind the demonstration, the iodide-catalyzed decomposition of hydrogen peroxide (along with some complicating side-reactions), is discussed in some detail.

中文翻译：

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大象的牙膏用作速率与温度的定性演示

流行的大象牙膏示范可用于定性证明温度对反应速率的影响。我们的版本旨在简化执行过程，并且几乎不需要上课时间。在容易达到的温度（冰和环境温度）下进行两次反应，后者的速度大约快三倍。详细讨论了演示背后的反应，即碘化物催化的过氧化氢分解（以及一些复杂的副反应）。