D.C. SOURCE

1
ELECTROLYSIS OF A SALT SLIDE ONE OVERVIEW ANIMAT
ION
THIS COULD BE A HEART CHARM BRACELET PIECE TO BE
GOLD PLATED
D.C. SOURCE (BATTERY)
2e-
2e-
Cl2

THE CATHODE IS A CHEAP PIECE OF CONDUCTIVE
MATERIAL. THIS COULD BE ANY CONDUCTIVE (METAL) IN
JEWELRY TO BE GOLD PLATED.
Au3
-
-
-
THE ANODE IS SOLID Pt or GRAPHITE,AND DOES NOT
REACT IN REDOX (INERT)
-

-

Cl-
THE ELECTROLYTE SOLUTION, USUALLY H2SO4
THE SOURCE OF GOLD IS AuCl3 ( THE THREE CHLORIDES
ARE -1 EACH SO THE Au MUST BE 3.
2
ELECTROLYSIS, SALT SLIDE TWO NON SPONTANEOUS
OXIDATION AT ANODE
D.C. SOURCE (BATTERY)
Cl2 (DEADLY Cl2 GAS BUBBLES OUT AT ANODE.)

Au3
-
-
-
The anode (PLATINUM) IS ELECTRON POOR DUE THE DC
SOURCE PUMPING OUT ELECTRONS. THE CHLORIDE IONS
ARE ATTRACTED TO THE CHARGE OF THE
ANODE.REMEMBER HALOGENS REACT IN PAIRS!
Cl-

-
An important characteristic of the electrolytic
cell is that the oxidation of a LESS active
non-metal (bottom position on table J).
Cl-

Cl-
OXIDATION AT ANODE
3
ELECTROLYSIS, OF A SALT SLIDE THREE ELECTRON
FLOW
D.C. SOURCE (BATTERY)
2e-
2e-
Cl2
THE D.C. SOURCE ACTIVLEY PUMPS ELECTRONS OUT
OF THE ANODE CAUSING IT TO BE RELATIVLEY POSITIVE
COMPARED TO THE CATHODE.
THE D.C. SOURCE ACTIVLEY PUMPS ELECTRONS ITO
THE CATHODE, CAUSING IT TO BE NEGATIVE RELATIVE
TO THE ANODE. THIS HIGH DENSITY OF ELECTRONS AT
THE CATHODE WILL FORCE A REDUCTION TO OCCUR.

Au3
-
-
-
Cl-

-
-
Cl-

Cl-
4
ELECTROLYSIS SALT SLIDE FOUR NON SPONTANEOUS
REDUCTION AT CATHODE
THE SOLID GOLD THAT WAS PRODUCED DURING REDUCTION
ELECTROPLATES THE CATHODE AS SOLID GOLD
D.C. SOURCE (BATTERY)
2e-
2e-
Cl2

-
Au
Au3
THE CHLORIDE IONS CONTINUE TO MIGRATE TO THE
ANODE AS THE GOLD MIGRATES TO THE ANODE.
-
Cl-

-
Cl-
THE GOLD(III) CATIONS MIGRATE TO THE ELECTRON
RICH, NEGATIVELY CHARGED CATHODE WHERE THEY WILL
BE FORCED TO BE REDUCED TO Au0 SOLID.

Cl-
REDUCTION AT CATHODE
5
BALANCING THE HALF REACTIONS
2Au3 (aq) 6Cl-(aq)
3Cl20 (g)
2Au3

?
(aq)
6
REVIEW OF ELECTROCHEMICAL CELL TYPES VOLTAIC CELL ELECTROLYTIC CELL
SPONTANEITY SPONTANEOUS NOT SPONTANEOUS
METAL OXIDIZED TOP OF TABLE J BOTTOM OF J
CATHODE REDUCTION IN BOTH CELLS POSITIVESPONTANEOUS REDUCTION CONSUMES ELECTRONS. NEGATIVE DC SOURCE (BATTERY) FORCES ELECTRONS HERE.
ANODE OXIDATION IN BOTH CELLS NEGATIVE SPONTANEOUS OXIDATION SUPPLIES ELECTRONS HERE. POSITIVE D.C. SOURCE PULLS ELECTRONS OUT.
ENERGY EXOTHERMIC ENDOTHERMIC
ELECTRON FLOW FROM ANODE TO CATHODE FROM ANODE TO CATHODE
ELECTRON GRADIENT HIGH TO LOW ENERGY LOW TO HIGH ENERGY