Other slides in this set

Slide 2

Preview of page 2

Here's a taster:

FUEL CELLS
· What is a fuel cell?
· A electrochemical device that uses a
chemical reaction between hydrogen
and oxygen (or another oxidising
agent) to produce electricity and water.
· Who invented them?
· Fuel cells were invented by Sir William
Grove in 1842.
· At first fuel cells weren't efficient
enough.
· Modern fuel cells
· Modern fuel cells are based on
hydrogen or `hydrogen rich' reactants
such as methanol.
· Modern fuel cells were used in the
space shuttle launch.…read more

Slide 3

Preview of page 3

Here's a taster:

A SIMPLE FUEL CELL CONSISTS OF TWO ELECTRODES; AN ANODE
AND A CATHODE SEPARATED BY AN ELECTROLYTE .
· What happens at the Anode?
· Hydrogen will react with a catalyst to create one
proton (H+ Ion) and one electron (e- ). The proton
will then pass through the electrolyte while the
electron travels around the circuit therefore
creating a current.
· What happens at the Cathode?
· Oxygen will react with the proton (H+ Ion) and
the electron (e- ) to form water and a useful
amount of thermal energy.
(This cell will generate about 1.23v ,as shown in the
previous slide, which is enough to power one light
bulb)…read more

Slide 4

Preview of page 4

Here's a taster:

MAKING A FUEL CELL
Questions for the following
experiment
Pb Pb2+ + 2e-
PbO2 + 4H+ +2e- Pb2+ + 2H2O
What is the overall ionic equation?
Pb + PbO2 + 4H+ 2Pb2+ + 2H2O
What is formed at each electrode
and
give the equations
Hydrogen is formed at the cathode
and oxygen is formed at the anode.
2H+ + 2e­ H2
4OH­ 2H2O + O2 + 4e…read more

Slide 5

Preview of page 5

Here's a taster:

E CELL = E POSITIVE TERMINAL ­ E NEGATIVE
TERMINAL
2H2O + 2e- H2 + 2OH- E = -0.83V (negative
terminal)
½O2 + H2O + 2e- 2OH- E = +0.40 (positive
terminal)
E cell= +0.40 - -0.83 = 1.23V
Using the top right-bottom left rule you can
deduce the Cell reaction
Therefore, combining the two equations we get:
- - - -
· H + 2OH + ½O + H O + 2e 2OH + 2H O + 2e
2 2 2 2
Overall reaction:
· H + ½O H O
2 2 2
The flow of electrons from hydrogen to oxygen
creates a voltage.…read more

Slide 6

Preview of page 6

Here's a taster:

DIFFERENT TYPES OF FUEL CELLS
Fuel cells require a
Hydrogen- rich
fuel source such as
Hydrogen gas,
Methanol or
Natural gas.
However,
Methanol and
Natural gas create
Pollutants such as
CO2. One
advantage of these
is that they're
easier to store and
can be generated
from Biomass so
this overcomes the
problem of using
up all the finite
sources.…read more

Slide 7

Preview of page 7
Preview of page 7

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all resources »