The Electrochemical Series
Intermediate 2 Chemistry
Unit 3(c)
V
• If you set up this experiment, what would happen?
V
Salt solution
• What name is given to a solution like the one
above?
A cell
ELECTRONS
V
The metal HIGHER in the
electrochemical series
LOSES electrons to the
metal lower down.
ELECTRONS flow through
the wires.
IONS
IONS flow through the
solution to complete the
circuit.
The electrochemical series (ECS)
Aluminium
Zinc
Iron
Tin
Lead
Electrons flow from one metal to another to
create a voltage
Imagine you connect different metals to
TIN...
Mg
Cu
Sn
1.2 V
-0.5 V
0V
+ve – the metal is
above the other
metal in the ECS
-ve – the metal is
below the other
metal in the ECS
0 – the metal is the
same as the other
metal
Mg
Cu
Sn
1.2 V
-0.5 V
0V
large number –
large gap
between the
metals in the ECS
small number –
small gap
between the
metals in the ECS
Above tin
Large gap
Below tin
Small gap
Magnesium
Aluminium
Zinc
Iron
Tin
Lead
Copper
The problem...
• You have a selection of different metals, but
you don’t know what any of them are
• By connecting them together in cells:
– rank them according to their position in the ECS
– suggest what metal each one actually is
*Tip – the metal you start with (and are comparing to)
should always be connected to the +ve terminal of the
voltmeter
Half cells