Practical work supporting learning
The basic electrolysis practical we have looked at so far must be integrated into progression within science. There are some assumptions that are made: Can the students set-up a circuit correctly? Do they understand what constitutes a solution?
The last question is particularly important. Students need to have an understanding of ions before they can begin to explain the electrolysis. Most students will understand that sodium chloride makes sodium ions (Na+) and chloride ion (Cl-) but not that water can dissociate into H+ and OH-.
This practical also fits into the application of REDOX (REDuction-OXidation) reactions. Oxidation reactions are the loss of electrons, reduction is gain of electrons. This is often summarised as the mnemonic OILRIG: Oxidation Is Loss, Reduction Is Gain (of electrons).
Think about how the practical work fits into the science that learners need to understand, and how you might stage the practical to support this. Recipes and sets of instructions can be useful to gain an understanding of how to set up a practical, but students need to move away from this to be able to apply their learning. We are giving a number of different practicals which can be used, so that students can have a chance to practice their skills. These could be set as more of an investigation, or students could design the activity (or parts of it) themselves.
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