Nicola Goodwin
S11
How Does Changing The Amount of Electricity Effect How Much Copper is
Deposited During Electrolysis?
Plan
I am going to investigate how changing the current, effects how much copper is deposited during electrolysis. The equipment I will use is as follows: -
A DC power pack An ammeter 125cm³ of Copper Sulphate (CuSO4) solution
A rheostat A stopwatch A thermometer Some wires
2 Copper sheets (for the anode and cathode) A beaker of water A beaker of propanone
Piece of card with two slots about 4cm apart Sandpaper Electric Balance Crocodile Clips
I will set up the equipment as follows: -
I will cut two pieces of copper both 8cm long and 2.5cm wide. I will then sand both pieces of copper with the sand paper, so that they have a rougher edge, then I will dip it into the beaker of water then in the beaker of propanone. Then I will let it dry in the air. Doing this will ensure the anode isn’t greasy, and has a rough edge, so that the copper will be able to stick to it. Once I have done this I will weigh both the anode and the cathode and record the weight. I will handle both electrodes with care to ensure they do not get re-greased. I will then put the electrolytes through the card; I will do this to control the distance they are apart from each other to ensure a fair test. I will continue to set up the equipment as it is in the above diagram. Then I will measure the temperature of the copper Sulphate solution, once I have done this I will turn the power pack on ensuring the power supply is on D.C. I will then use whatever current the power pack gives me, as it is very difficult to find a specific current using the rheostat. As soon as the current is set I will turn on the stopwatch and time it for 8minutes (480 secs). I will keep measuring the temperature of the copper Sulphate throughout the experiment to ensure it is kept at a constant. When the 8minutes are up, I will switch off the power supply, and very carefully take the anode and cathode out of the solution. I will then dip each one in the beaker of water followed by the beaker of propanone. I will allow them to dry, and then measure their masses again. I expect that the cathode should get heavier, by the same amount of grams as the anode got lighter. I will record my results in a table like this: -