Mnemonics for Electrolysis
These cards show you all the mnemonics etc. that I use to help me remember where things go in electrolysis, because it all gets abit complicated.
Hope this helps
Positive and Negative Electrodes
Remember PANIC: Positive Anode, Negative is Cathode
Metals form Positive ions. They are attracted to the Negative Cathode.
Non-Metals form Negative ions. They are attracted to the Positive anode.
Remember, N N for Negative Non-metals
What Happens at the Electrodes
At the positive anode, the negatively charged non-metals lose electrons to become neutral. They are OXIDISED.
At the negative cathode, the positively charged metals gain electrons to become neutral. They are REDUCED.
Use OIL RIG to remember this:
OXIDATION IS LOSING, REDUCTION IS GAINING
Remember ANODE ARROW, because the arrow comes sooner in the anode equations.
You need the substance, eg Cl- (it's always negative at the anode) then the arrow then the substance, eg Cl2 and electrons e-
2Cl- --> Cl2 + 2e- Remember to make it balance because Chlorine is diatomic - it always forms as Cl2
At the cathode, the arrow comes at the end. The substance is always positive.
2H+ + 2e- --> H2. Again, hydrogen is diatomic so make it balance.
To remember what goes where during electroplating:
Coated Cathode. The thing to be coated at the cathode (negative)
Actual Anode The actual metal to coat with at the anode.