Copper
Silver
Gold
Potassium
Least reactive
Electrical flow through metals work like this: the current in the metal is carried by electrons and will only flow if there charges which can move freely. Metals contain a sea of electrons (which are negatively charged) and which flow throughout the metal. This is what allows electric current to flow so well in all metals.
An electrode is a component of an electric circuit that connects the wiring of the circuit to a gas or electrolyte. A compound that conducts in a solution is called an electrolyte. The electrically positive electrode is called the anode and the negative electrode the cathode. When a positive and a negative electrode are placed in a solution containing ions, and an electric potential is applied to the electrodes, the positively charged ions move towards the negative electrode, and the negatively charged ions to the positive electrode. As a result, an electric current flows between the electrodes. The strength of the current depends on the electric potential between the electrodes and the concentration of ions in the solution.
Ionization is the formation of electrically charges atoms or molecules. Atoms are electrically neutral; the electrons that bear the negative charge are equal in number to the protons in the nucleus bearing the positive charge. When sodium combines with chlorine, for example, to form sodium chloride, each sodium atom transfers an electron to a chlorine atom, so it forms a sodium ion with a positive charge and a chloride ion with a negative charge.
I was given six metals to test and see which gave out the most voltage in a solution. The metals are: copper, zinc, aluminium, magnesium, lead, and tin. There was three different ways I could have done this. I could have tested two different metals in different solutions and see which solution gave out the most voltage, I could have used the same metals and same solution and dilute it, or I could have used the same solution and try different metals, I used the last method because I thought it would be more logical.
My first actual plan was to test five metals: calcium, aluminium, zinc, magnesium, and iron. I wouldn’t try potassium, sodium, or lithium because I knew they would blow up, (because of previous experiments) and be no use. Firstly I would test aluminium and calcium together five times, then zinc and iron five times then swap them around and then see the results to see which combination gives out the most power. I wasn’t going to test anything lower than iron because I don’t think it will be worth it and it will take a long time to conduct and not give out a lot of power.
Apparatus
The following apparatus will be used: a beaker, hydrochloric acid, voltmeter, 2 clip wires and copper, zinc, aluminium, magnesium, lead, and tin.
Diagram
Prediction
I think aluminium and magnesium would give out the most power because they are higher than zinc and iron in the reactivity series, therefore it would be more appropriate to use aluminium and magnesium as it would be likely to give out more power. If magnesium explodes then I think zinc would be the next choice.
Health and safety
This is always important when working in a science lab. You should wash your hands after handling acids and other types of chemicals, and wear gloves if necessary. Don’t run around the lab, point out any safety hazards to the people around you, and don’t pour chemical contents into a sink.
Method
I started the experiment like this: I poured 25ml of hydrochloric acid into a beaker, (I used this acid because I was told that it was the best one to use). Then I connected the voltmeter and the two wires together and placed one strip of copper onto both clips. I then placed both clips (with two strips of copper on them) into the beaker and held them apart. I recorded the volts given out and took the strips of copper out again. I did this five times with each metal to make it a fair test.
Results
Magnesium turned out the best so I was lucky I did test this metal, the hydrochloric acid fizzed up when I tested it. Aluminium was second and but zinc was close behind. Lead and tin was literally useless, as it didn’t give out hardly any power at all.
Conclusion
Magnesium by far gave out a lot more power than the other five metal. The highest voltage it gave out was 0.53 and aluminium gave out 0.08, as you can see there is a big drop here. Even though aluminium is right behind magnesium in the reactivity series, in this experiment it looks likes it is much more behind. I think the results were accurate because it was done five times with each metal, which made it fair.
Evaluation
The method in which this experiment was done was ok but I think it would have been better if I got to choose how to do it and what metals to use. The quality of the results I think were considerably reasonable. But the results I got with lead was silly, it was a waste of time trying lead as it didn’t give out hardly anything but if I had given it more time, then maybe it would have done better. To improve the way the experiment was done: I could have tried different acids to test the metals, use a wider range of metals to test, use a better and more reliable voltmeter, and give the metals more time to react with the solution. But this experiment was a short and simple experiment to find out which metals gave out the most voltage.