reduction

An Experimental Demonstration of Hess's Law

Philip Penketh | Sun, 08/02/2020 - 10:03

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The application of Hess's Law frequently presents students with conceptual problems. This series of experiments confirms Hess's Law and offers a robust understanding of this principle. This can be done as a demo completed by the teacher or as a lab with groups of students.

Reduction of Permanganate Ion by Acids in Rhubarb, Apples, and Candy

Tom Kuntzleman | Mon, 06/05/2017 - 17:00

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If rhubarb stem is placed in a solution of permanganate, the purple permanganate ion is reduced to the colorless Mn²⁺ ion. It is thought that the oxalic acid present in rhubarb causes this reduction. The investigations presented in this post provide evidence that this may not be the whole story...