Karteikarten
Electrolysis
Karten in diesem Stapel (7)
- 1ElectrolysisThe breaking down of a molton or aqueous ionic compound using electricity
- 2Molten on the left. Solution on the rightIonic compounds are made up of positive and negative ions. But in order for them to conduct electricity, they have to be able to move around.
- 3Why does the ionic compound have to be in liquid form?Solid ions are fixed in place and cannot move and carry charge. In liquid form, the charged particles can move past each other and therefore conduct electricity.
- 4Electrolysis of a molten ionic compoundExample: lead bromine, starts off solid in the ionic compound. The compound is heated to turn the lead bromide into a molten form. After heating, the electric current is flowing, and the negative ions are attracted to the anode, whereas the positive ions are attracted to the cathode. As a result, the compound breaks apart: lead forms at the cathode and bromine forms at the anode
- 5Equations for what happens at each electrode: half equations At the anodeEquation: PbBr2(l) -->Pb(l/s) + Br2(g).
Half equations.
At the anode: non-metal will always form at anode. The bromine forms here, and so start of with Br-. But as there are 2, we have to balance out the equation:
2Br- -->Br2 +
We then have to balance out the negative charge by adding 2 electrons, taken from the electric flow.
2Br- -->Br2 + 2e- - 6Half equations At the cathodeThe metal will always be attracted to the cathode. This time we start with Pb2+. On this side the lead ions are gaining two electrons: Pb2+ + 2e-
They then form the lead metal:
Pb2+ + 2e- --> Pb - 7—
Informationen
- Beschreibung
- Electrolysis, chemistry 3-- chemicals of the natural environment
- Erstellt von
- Jamine Shaw
- Aufrufe
- 135
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