Method
The experiment was set up as shown in the diagram. The experiment will be using 100cm3 Hydrochloric acid and will be changing the concentration every time by diluting the acid by substituting 10cm3 of acid for 10cm3 of water. We will do this process until we get 60cm3 of acid and 40cm3 of water, this will give me enough results to plot a table.
To make this a fair test I will measure the Magnesium strip as accurately as I can. This will make my experiment a fair test also I will try to keep the beaker at the temperature by leaving at room temperature. To make sure I have no major injuries in my experiment, I will insure I wipe up any spills immediately because hydrochloric acid is a corrosive chemical, which will burn the skin and wear the safety classes that are provided.
Prediction
I think that the more concentrated hydrochloric acid will react with the Magnesium strip in a shorter time.
I think this because in a more concentrated acid there are more particles to collide with the magnesium therefore making the reaction faster.
In everyday lives we see rates of reaction, one of these rates of reaction is the plastic bag. The plastic bag has a very slow rate of reaction. We know this because it does not react with air or water. Which means it’s a nasty piece of litter!
In my prediction I said that the higher concentrated acid would give the fastest rate of reaction in the shortest time. I know this from a past experiment. The past experiment included: -
Sodium thiosulphate + hydrochloric acid Sulphur + Sodium Chloride + sulphur dioxide +water
Graphs
Results table
Conclusion
My graph of time against concentration is a straight line. I also have a graph of the rate against concentration of acid. This graph is a sigmoid.
This shows my results were quite accurate as if they weren’t the graph wouldn’t look right (i.e anomalous results stand out on graphs).
My prediction was right from another experiment the results were very similar. My overall conclusion is that the concentration is proportional to the time, but the Concentration is inversely proportional to the Rate.
Evaluation
To improve my experiment, I would make it more accurate. I would do this by asking for a second opinion on the length of the Magnesium, and by using a more precise measuring tool. I believe that this would have made the experiment a lot fairer and accurate. Also, I could improve it by making sure that the beakers were all dry before I put the Hydrochloric acid into them. This would have given me a more specific result.
To extend my work, I could’ve gone lower in the concentration. I could’ve gone to just water to check if there was a trend in the results.
Having found this out, I would like to do another experiment to see if the results are similar.