Electrolysis sim
The anode is joined to the positive terminal (red) and attracts anions; the cathode is joined to the negative terminal (black) and attracts cations.
Electrolysis · covers the GCSE, IGCSE, O-Level topic
What the sim shows
The anode is joined to the positive terminal (red) and attracts anions; the cathode is joined to the negative terminal (black) and attracts cations. The cell holds 100 cm³ of electrolyte, and each tube holds 20 cm³; once a tube is full, the extra gas bubbles out of its mouth. The amounts come from the charge: moles of electrons = current × time ÷ 96500. Hydrogen and chlorine need 2 electrons a molecule, oxygen needs 4, so hydrogen and oxygen collect 2 to 1. In a real cell a little chlorine dissolves, so slightly less collects than hydrogen. The clock runs twenty times faster than real time.
- Positive terminal and anode
- Negative terminal and cathode
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
More chemistry sims
- Displacement simA more reactive metal displaces a less reactive metal from a solution of its salt: the less reactive metal coats the piece, and its coloured ions (blu
- Acid–base titration simOpen the burette: pH crawls, leaps at 25.00 cm³, and phenolphthalein turns pink.
- Rate of reaction simWarm the water bath and the gas syringe fills faster, modelled with the Arrhenius equation.
- Testing for cations: NaOH(aq) and NH₃(aq) simCarry a real dropper to eight cation solutions: watch each precipitate form, stay or dissolve in excess, and warm ammonium to turn damp red litmus blue.
- Acid rain simDrag sulfur dioxide and nitrogen dioxide into a cloud and watch the rain's pH fall, a marble statue lose mass and a lake turn acidic; then lime the lake and clean up the air.
- Addition polymerisation simJoin ethene, propene, chloroethene or tetrafluoroethene monomers into a chain, see the bracketed repeat unit with n, and work back from a polymer chain to its monomer.