Electrolysis
of Water
Problem:
How can you perform Electrolysis of water
to produce Hydrogen and Oxygen?
Research the Problem:
Electrolisis is Chemical change, especially
decomposition, produced in an electrolyte by an electric current.
Electrolytes dissolve by dissociation. That is when the molecules
of the substance break down into charged particles called ions.
An ion with a negative charge is called an anion because it is
drawn through the solution to the positive charge on the anode.
A particle with a positive charge is called a cation. It moves
through the solution to the cathode. Water has its solvent properties
because it is polar. The molecule has charged ends (+ and -).
These charged ends react with charges on other polar substances
to dissolve them. They do so by taking hydrogen atoms from the
substance to form hydronium ions. The word electrolysis means
the process of breaking molecules to smaller components by using
an electric current. Positive and negative poles of a DC electric
source such as a battery can absorb opposite ions of an electrolyte
causing separation of ions and creation of a new substance.
Hypothesis: Adding
some Sulfuric Acid as electrolyte will increase conductivity
of water and creation of Hydrogen and Oxigen gases.
Experiment:
In this experiment, initially we used
two copper wires, one twelve-volt battery, and some drinking
water to do the tests. The process was slow and caused excessive
amounts of corrosion on the copper wires and discoloration in
the water. To avoid corrosion of electrodes and discoloration
of water, we repeated the test using Graphit Rods as electrodes.
Also to speed up the process we added some Sulfuric Acid to the
water as electrolyte.
Materials
Used:
Copper Wire, Graphite Rods, Sulfuric Acid,
Test Tubes, Beaker, Water
Procedure:
Fillup ¼ of beaker with clear watter,
secure two test tubes filled with water in the beaker in a way
that test tubes are up-side down over the beaker. Mount the wires
or electrodes that you have prepared and then connect the electricity.
Check the produced hydrogen and oxygen
gasses in five minutes. Repeat the test with different electrodes
and different amounts of electrolytes and record the results
in the table below. You may want to repeat the experiment with
different electrods. (Electrod is only the area that has contact
with water, not the part that has insulator or plastic cover.
In the above picture electrodes are identified with yellow color).
Electrode |
No Additive |
5% Salt |
5% Sulfuric Acid |
10% Sulfuric Acid |
Aluminum |
|
|
|
|
Steel |
|
|
|
|
Platinum |
|
|
|
|
Copper |
|
|
|
|
Graphite |
|
|
|
|
Record and Analyze Date:
Credits, References,
Sources: Comptons Online Encyclopedia
|