Electrolysis vs Electrochemical cells.

Electrolysis

Copper + Chlorine gas --> copper chloride (spontaneous reaction)

Copper + Chlorine gas <-- Copper chloride (non-spontaneous reaction)
electrolysis


Electrochemical cells

This works by combining two REDOX half cells containing metals of different reactivity.

example: Zn/Zn2+ half cell connected to a Cu/Cu2+ half cell.

When these two half cells are connected, the Zn half cell undergoes oxidation because Zn is more reactive that Cu.

Zinc half cell:

Zn --> Zn2+ + 2e- -this is oxidation, LEOA, anode, and will be negative as electrons are being released.

Copper half cell:

Cu2+ + 2e- --> Cu -this is reduction, GREC, cathode, and will be positive.