Electrolysis of Copper Sulphate Solution.
Extracts from this document...
Introduction
Electrolysis of Copper
Sulphate Solution
Introduction
In wires, current is a flow of electrons, in liquids, the current is a flow of ions. The ions have a positive or negative charge and the electrons have a negative charge. Ions can move about if the substance is either dissolved or melted.
Negatively charged ions move to the positive electrode and the positively charged move towards the negatively charged electrode. When this occurs, the substance has been split in to two substances, this is called electrolysis.
Copper sulphate Solution is split in to copper ions, which are positively charged and go to the negative electrode and into Sulphate, which is negatively charged and goes to the positive electrode.
Variables
The variables I could investigate are:
- The current
The more current, the more copper will be deposited
- The voltage
The more voltage, the more copper will be produced
- The concentration
The higher the concentration, the more ions will be present
- Volume of solution
The more solution, the more ions to carry the current
- Distance between the electrodes
The further apart the electrodes, the further the current has to travel
- Depth of electrodes in solution
The larger surface area available for the ions to go too
Middle
First I will collect all my apparatusThen I will set up my equipment as follows
...read more.
- Then I will collect 100ml of copper sulphate and put it in the circuit
- Then I will read the ammeter and write it in my table of results
- After that I will replace 10ml of the copper sulphate with 10ml of water
- I will do this six different times and replace 10ml of copper sulphate with 10ml of water each time
Results
Volume of Copper Sulphate(ml) | Volume of Water(ml) | Current | (amps) | Average |
100 | 0 | 0.12 | 0.13 | 0.12 |
90 | 10 | 0.11 | 0.09 | 0.10 |
80 | 20 | 0.11 | 0.09 | 0.10 |
70 | 30 | 0.10 | 0.08 | 0.9 |
60 | 40 | 0.08 | 0.07 | 0.75 |
50 | 50 | 0.046 | 0.06 | 0.54 |
Fair Test
To make it reliable I will repeat my experiment six times. I will also try and do all of my experiment on the same day and use the same equipment. I will also try to use the same batch of copper sulphate. I will also keep the total volume the same and the voltage setting, the distance between the electrodes. I will also keep the current and the depth of the electrode in the solution the same.
Safety
To make my experiment safe I will not put the power pack on
Conclusion
Copper Sulphate(ml) | Current(amps) |
40 | 0.8 |
50 | 0.046 |
Sometimes they went down quite evenly and others they drop quite dramatically. I could make our results more accurate by measuring the current more precisely and repeating the experiment a few more times. I got one anomalous result, which I am not going to concentrate on because it is only one out of six and because our experiment could be greatly improved.
I could avoid them next time by making our experiment more accurate and reliable. I could improve the experiment:
- By measuring the water and copper sulphate more accurately
- By using the same batch of copper sulphate, as the lab technician had to make another batch
- By doing it all on the same day
- Using the same equipment
My conclusion is valid because of my results and my graph, which backs it up and my scientific evidence. They are valid over the range of 100% to 50%. I could extend our investigation of the same variable by using a different method to collect relevant information. I could investigate the change in mass, by weighing the electrode. As the copper and the sulphate separate the mass of the beaker and its contents should change as the copper and sulphate would be on the electrodes.
This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics section.
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