I am going to find out how fast or slow a reaction will go according to how dilute or concentrated the catalyst is.
I am going to make the method safe by always wearing safety glasses at all times to protect my eyes from the catalysts.
In this investigation for my catalyst I will use some celery, which will be mashed up so the surface area of it is increased, therefore the reaction will be faster.
Equipment
- 100ml gas cylinder.
- Clamp.
Method
- Set up equipment.
- Mash some celery using a motar and prisel
- Weigh out 2 grams of mashed celery using some electric scales.
- Put in to a conical flask which has been connected to a gas cylinder, which also gas been held by a clamp which is connected to a stand.
- Then measure out 20ml of a certain concentration of hydrogen peroxide and add to the celery.
- Place bung on top of conical flask.
- Start timer.
- Record results.
I am going to do this investigation using the method shown above.
Before I do the main experiment I am going to do a preliminary experiment. This will help me in my final experiment, because then I will have a rough idea of how my results will be like and what to improve in my final experiment. My preliminary test went quite well.
These are the results I got for my preliminary test:
From this preliminary test I found out that the less the concentration of hydrogen peroxide there is the less amount of oxygen is made and obtained. Therefore the higher the concentration of hydrogen peroxide, the more oxygen is made and obtained.
I predict that in the experiments that I put more concentrated hydrogen peroxide in with the celery, the more oxygen will be made and obtained, and vice-versa. The results that are obtained will be very similar to the results I got in my preliminary test. I think the more concentrated the hydrogen peroxide is the more oxygen will be obtained because the higher the concentration is the faster the reaction will be, and because I am only seeing how much oxygen I can obtain in just 60 seconds, the higher concentration will make more oxygen in so little time.
In my investigation I am going to observe how much oxygen is made from the celery and hydrogen peroxide reacting with each other. To make it a fair test I am going to use clean equipment on every experiment and I am going to use 20ml of hydrogen peroxide and 2 grams of celery in every experiment. The only thing I am going to change is the concentration of the hydrogen peroxide.
For every different concentration, I will repeat that experiment 3 times. I will repeat it 3 times so that when I get an average it will be more accurate. I will take my readings from the experiments every 10 seconds.
These are the results I obtained from my final experiment:
The results I obtained are very similar to the results that I predicted. In my prediction I wrote that in the experiments that I put more concentrated hydrogen peroxide in with the celery, the more oxygen will be made and obtained, and vice-versa. The results that are obtained will be very similar to the results I got in my preliminary test. This prediction that I made was very accurate to the results I got.
From the table and graphs I can calculate the rate of reaction for each experiment. First I got the averages from each experiment divided them by the time when they were taken.
Here is a table to show how I worked out the rate of reaction for each experiment:
To work out the average rate of reaction for each experiment you have to add together all the numbers in the right hand side columns and divide by 6.
Here is another table to show the average rate of reaction for each experiment:
These tables show the average rate of reaction to 3sf for each experiment.
I thought that the experiments that I did was very successful. The experiments that I did fit with the prediction that I made, which was that the results I got would be similar to my preliminary test results.
If I had to repeat the experiment, the changes which I would make would be:
- I would increase the time that I got. This would allow me to concentrate more, which will help me make the results that were obtained more reliable and accurate.
- I would use another more effective way to grind up the celery. This would make the result slightly fairer because then all of the celery used will be grinded to the same amount.
- I would write down the readings to the nearest 0.1 ml. This would give me a more accurate average.
- I would repeat the experiment more times to also get a more accurate average.
The only difficulties I got during the experiments was that as soon as I added the hydrogen peroxide to the celery it took me about 1 second to place the bung on top of the conical flask and when reading the results off of the 100ml gas cylinder it was quite hard to get a very accurate reading.
Finally to conclude this investigation I will state the fact I have learnt from doing this investigation:
- The higher the concentration of the hydrogen peroxide which is added to the celery is the higher the amount of oxygen is obtained in a small amount of time i.e. 1 minute.