Friday 29 July 2016

Electrochemical Cells

Today we made a Zinc-Copper cell and measured its voltage. We then put a group of them in series to amplify the voltage - this is called a battery.



There is a convention for how we write a "cell diagram" for this, and we will explore that more next week.

Standard electrode potentials are measured by setting up the hydrogen half-cell as the anode. The redox pair that you want to know the electrode potential for is then set up as the cathode, and the voltage recorded - this is the electrode potential for this particular redox pair.

Wednesday 6 July 2016

Oxidation-Reduction

Today we recalled the work we had done on: oxidants and reductants; observations and half equations; and oxidation numbers:





Friday 1 July 2016

Entropy

This video sums it up very nicely:






It is worthwhile knowing the sorts of questions we may be asked about entropy as well:


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