As I increase the concentration I know that this will increase the number of collisions in-between the particles. In the solution that I will make for my experiments, by making the solution more concentrated will have the effect of more particles knocking into one another and colliding. This will make the reaction more likely and also in a quicker time.
Basically this means the higher the concentration, the more squashed up the particles will be. Therefore there will be more collisions between the particles.
My preliminary test is to see if there are any faults with the experiment, and to also see if anything needs to be changed before the real experiment is conducted.
Preliminary Results
I did my preliminary experiment, and as you can see from the table there were some very big gaps, which I did not expect.
Apparatus List
1. Hydrochloric Acid ( 3 moles )
2. Water
3. Magnesium strip
4. 2 Beakers
5. Stop watch
6. Safety glasses
7. 1 Small test tube
Apparatus Diagram
Step by step
Step 1; First of all, you need to get all the apparatus, which I have listed.
Step 2; Now arrange the apparatus like it is shown above in the apparatus diagram.
Step 3; Ok, in one of the measuring beakers, measure 80ml of hydrochloric acid. Then pour the acid into the main beaker.
Step 4; Pick up the stop-watch and a piece of magnesium strip. Drop the strip of magnesium into the acid, as soon as the strip hits the acid press the start button on the stop watch.
Step 5; Press the stop button on the stop-watch when the magnesium piece has totally gone from inside the beaker and acid.
Step 6; Record the time on a table or somewhere.
Step 7; Clean out the apparatus, and then mixed together 70ml of acid with 10ml of water and start all over again.
Step 8; Keep on doing this until you get to the proportion of 10ml of acid to 70ml of water.
Step 9; You should have all the data you need now.
Step 10; Clear away all the apparatus and make sure the desk you were working at is tidying.
Fair Test
To make my experiment a fair test there will be a number of things that I must carry out. The first thing at I must do is to use all the same apparatus throughout the experiment. Also the magnesium strips that I put in the acid and water must be the same length, all the time. This length is two centimetres. The experiment should really be done in one lesson, if the experiment is done over two different lessons then the temperature may have changed, causing the reaction to be affected. Everything we do really should be the same, all of these combined will make this experiment a fair and accurate.
Safety
To make sure this experiment will be safe, you should:
- Make sure that the apparatus is set up in a way that, it will not fall off the table/desk that you are working at.
- Wear Safety glasses at all time to prevent any accidents happening such as acid going into the eyes.
- Beware of all the other experiments going on around you, as some will be involving bunsen burners.
- Do not try to clear up any broken glass on the floor.
- Make sure you wash your hands after handling all the acid and the magnesium strips.
Results
Conclusion
In my prediction I stated that the more acid in the concentration the quicker the reaction would take. Therefore the less acid in the concentration the slower the reaction would take. The evidence on the pages above supports my prediction with the less concentrated solution taking more the to react. I did my experiment and obtained enough results and evidence and by looking at both my preliminary and main results which are on the previous pages. The prediction that I made was right as you can see by the amount of results that I obtained, and all the background knowledge that went into it.
In my graph there is a pattern that the lower the concentration the more time it will take. And the same the other way.
Also in my prediction/background knowledge I said that the higher the concentration, the more particles that have more energy which then results in more collisions. Then when the particles collide with each other it is more likely that the solution will react rather than just bounce off of each other with no reaction occurring.
I know that when the magnesium strips react with hydrochloric acid, hydrogen is formed. This would then explain the bubbles which were being created when the reaction took place.
Evaluation
I think that the experiment that I conducted was very professional, and the evidence that I obtained was to a high standard, and is reliable as i followed this procedure to a good level. The evidence that I gathered was what I had been expecting from this experiment. The suitable of this procedure for obtaining the results prove to be beneficial for the experiment. I could improve my results for one;
I could of took three sets of data and then taken the average of them to come out with the best result possible,
Also I could have weighed the piece of magnesium instead of just measuring the length, this would of made my results even more accurate.
There is only one way which I could of provided more additional evidence would to be to measure the amount of hydrogen which was given out by the reaction. All I would have to do is to check that the magnesium strips were the same, and that I changed the concentration each time. The amount of Hydrogen produced in each reaction would be different as there are different concentration levels. Then by finding out how much hydrogen as given off I could then relate this to, the rate of reaction by the quicker the hydrogen was released the faster the rate of reaction would be.
The reliability of the evidence is sufficient to support the conclusion. The evidence of both my preliminary test and my actual test are very good and account for what I predicted.
