Electrolysis
This practical lesson covers:
- The electrolysis of aqueous solutions using inert electrodes
Investigating electrolysis of aqueous solutions
Aim
To investigate what happens when aqueous solutions are electrolysed using inert electrodes.
Background information
Electrolysis is a process in which electrical energy is used to drive a chemical reaction. In this practical, you will perform electrolysis on aqueous solutions of copper (II) chloride and sodium chloride using inert carbon electrodes. You will observe the formation of products at the electrodes and test the pH of the solutions after electrolysis using blue litmus paper. If the solution becomes acidic, the blue litmus paper will turn red, while if the solution becomes alkaline, the blue litmus paper will remain blue.
What is the purpose of using blue litmus paper in the experiment?
to determine the atomic number of carbon
to test the pH of the solution after electrolysis
to measure the voltage of the power supply
to observe the formation of bubbles at the anode
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What is the purpose of repeating the experiment with the sodium chloride solution?
to study the effects of high voltage power supply
to investigate the properties of sodium chloride solution
to compare the effects of different electrolytes
to determine the atomic number of sodium
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In electrolysis, what is the name of the negative electrode?
cathode
anode
electrolyte
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What happens at the anode during electrolysis?
at the anode, negative ions gain electrons
at the anode, negative ions lose electrons
at the anode, negative ions gain electrons
at the anode, positive ions gain electrons
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