The collision theory shows us that if there are more particles in the same amount of space then more collisions can take place and therefore more reaction takes place.
Method
What I will need:
Hydrochloric acid(2 mole)
Water(to dilute acid)
10ml testube
Magnesium(0.05g)
Beret Stop clock(sensitivity 1/10s)
Beaker
The first thing that I shall do is gather together all of my equipment and then set it all up. I will then measure out several short strips of magnesium ribbon (0.05g). I will then make several concentrations of HCL, 2M, 1.6M 1M, 0.5M, 0.2M. I will do this by mixing H20 with 2M HCL and that will give me the concentrations that I need.
2M = 100ml HCL
1.8M = 90ml HCL + 10ml H20
1.6M = 80ml HCL + 20ml H20
1.4M = 70ml HCL + 30ml H20
1.2M = 60ml HCL + 40ml H20
1M = 50ml HCL + 50ml H20
0.8M = 40ml HCL + 60ml H20
0.6M = 30ml HCL + 70ml H20
0.4M = 20ml HCL + 80ml H20
0.2M = 10ml HCL + 90ml H20
I will then measure out 10ml of the HCL solution, then I will add the Mg ribbon, I will try to pay special attention to getting the time exactly so that it is a fair test. I will time for 20 seconds and using the beret I will measure how much gas is given off. I will then repeat the experiment 3 time so that I can get even and average results.
Results
Graph to Show my Results
Conclusion
I can see fro my results that the more concentrated a solution the more gas that it gives off. I think that this is because, there were more particles in the solution and so there was a higher chance of the particles colliding, and when particles collide that is basically what a reaction is. It can be thought of as people in a room all running around, with only 2 people in the room, both running, then they can avoid hitting each other but if you were to put 50 people in that same room then it would be a lot harder not to hit each other (see FIG.1). So I can see that my prediction was indeed correct.
FIG.1
2M HCL 0.5M HCL
Evaluation
During this investigation there have not been any rouge results and all of our results were as we expected them to be. However our results could not be 100% accurate for several reasons such as our equipment was not 100% accurate, for example our measuring cylinders could have been off by some very small fraction and that could have amounted up. When the reaction takes place bubbles are given off ,which sometimes did stay around the Mg which therefore reduces the surface area of the Mg and so the HCL could not react properly so this could effect the results. We could have controlled the stirring of the solution because if this is not done properly it can lead to incorrect results. Using larger concentrations of acid would give a bigger more accurate conclusion instead of just using 10ml testubes use 1litre testubes, this way graphs would be more spaced out and give a more accurate reading.
