Plan: the experiment will be done using the apparatus shown above, and ready-made instructions of which I have to abide by.
Variables:
Possible variables, all of which will be kept the same apart from the concentration of the molar solution, and the time it will take for the production of 20mls of magnesium. As these 2 variables are the variables that we are conducting our experiment to measure.
Possible variables:
- Time it will take to produce 20mls of hydrogen
- Concentration of Solution
- Volume of Solution
- Temperature
- Size of Ribbon
- Type of Ribbon
To create a fair test, certain aspects of the experiment will remain the same while some key variables will be changed. The variable that will be changed is the concentration of the molar solution. This will hopefully give me a set of varied results from which I hope to make a conclusion. If any of the non-variables are changed it would mean that the test would not come out fair. For instance if one of the magnesium ribbons were larger than any other the surface area of the ribbon would be larger and therefore there would be more area for a reaction to occur. I will have to carry out my experiment in a controlled environment. Paying attention to all the variables making sure that they are not altered in any way to have an effect on the experiment.
Method:
To complete my experience and gain accurate results, I will use 10 different concentrations of solution. 10 mls acid - 0 mls water to 0 mls acid - 10 mls water.
Pieces of magnesium ribbon will be obtained and then cut to size with a pair of scissors and a ruler. This part of the preparation must be done accurately in order not to change the length or surface area of the magnesium ribbon.
I will use 10 mls of each specific concentration and will record the results that occur.
The magnesium ribbon will be placed into the conical flask and will be measured according to the time it takes for 20mls of hydrogen gas to be produced. This will be the procedure for the whole experiment. I will do this for each specific concentration. I will repeat the experiment 3 times, in order to produce an accurate set of results. I will then obtain an average reading for my results.
After the experiment has taken place and I have obtained my results. I will display the recorded results in a table. I will then work out my averages, so that I can display them in my graph.
- First of all, I made sure that the apparatus was set up in the correct way.
- I filled the measuring cylinder with water, turned it upside down and set it up according to the experiments needs.
- I put in the right concentration of solution in the conical flask.
- I then put the magnesium strip into the flask and sealed the flask tightly so that no hydrogen gas could escape during the experiment.
- I timed each experiment from start to finish, making sure that each experiment was recorded precisely at the time when 20mls of acid had been produced. The results were recorded the results in a table.
- I repeated this procedure until I had completed and tested each and every solution.
- I repeated the test three times to help produce more accurate readings.
Safety:
Throughout the experiment, safety should always be taken into account. Therefore, while handling hydrochloric acid goggles should be worn at all times. I should also make sure that spillages should be cleaned up accordingly. I will also make sure whilst obtaining my mixture that, my measurements for the solutions are perfect. In order to achieve accurate results, I shall make sure that all the equipment is clean before and after use.
Hypothesis/Prediction:
I predict that the higher the concentration of the acid the faster the rate of reaction will be. I predict this due to my preliminary work. Which states that the higher the concentration of acid the greater the number of acid molecules in the volume. This means that there are more acid molecules colliding with the particles on the surface of the reactant. Thus, increasing the rate of reaction.
Results:
Graph x2:
Conclusion:
We can conclude that these results are accurate as they show a general trend, and they are very close to the line of best fit. The results, which have been obtained from the experiment, clearly show that as concentration of hydrochloric acid increases, the reaction time decreases. This is also shown in my prediction and hypothesis, which explains why the experiment went so well.
The results have appeared as they are due to the fact that as the hydrochloric concentration is increased the reaction is greater and at a faster rate, due to the increased chance of colliding ions.
All the evidence that I have used to make a conclusion from is accurate and has proven to be reliable, as they have given accurate results.
Evaluation:
I believe that the experiment went well. I collected sufficient data in order for the experiment to be carried out fairly and precisely. Everything was successful and my final results were proved to be accurate and collaborated with my predictions. The chance of this was increased due to making the test fair and, repeating the test to gain precise data.
I believe that over a longer period of time with more concentrations of solutions the experiment could have been done to give a more accurate conclusion, it will also carry more precise results. I could have also organised the experiment a little better by making sure everything is done perfectly and precisely. Apart from this there does not seem to be anything wrong with my results as they clearly show the motive of the whole experiment.
