Investigating Electrolysis with Inert Electrodes

Ever wondered what happens when you pass electricity through different solutions? This practical lets you find out by investigating electrolysis using copper (II) sulfate and sodium chloride solutions with inert electrodes (carbon rods that don't react).

Safety comes first - you must wear eye protection throughout this experiment. The setup is straightforward: you'll use carbon electrodes connected to a 12V DC power supply, with test tubes to collect any gases produced.

For the copper (II) sulfate solution, you'll fill a beaker with the solution and insert two graphite rods. Connect one to the negative terminal (cathode) and one to the positive terminal (anode) of your power supply. The clever bit is using inverted test tubes filled with the solution to collect gases at each electrode.

When you turn on the power, oxygen gas should form at the positive electrode. You can test this by carefully holding a glowing splint just inside the test tube - if it relights, you've successfully produced oxygen!

Top Tip: Make sure your electrodes don't touch each other, or you'll short-circuit the experiment and miss all the exciting chemistry happening!

Understanding Your Results

The electrolysis process breaks down the copper (II) sulfate solution into different products at each electrode. At the positive electrode (anode), you'll see oxygen bubbles forming, which you can confirm with the glowing splint test.

This practical teaches you essential skills for identifying gases and using appropriate techniques safely. The inert electrodes (carbon/graphite) are crucial because they don't interfere with the reactions - they just conduct electricity.

When you extend this to sodium chloride solution, you'll see different results, helping you understand how different compounds behave during electrolysis. This knowledge is fundamental for understanding industrial processes and chemical reactions.

Remember: Always rinse any solution off your hands immediately and check all electrical connections if you don't see bubbles forming.