We started with 50 cm3 and 0cm3 of water. We discovered that the reaction happened to fast so we tried 45cm3 and 5cm3 of water. We did all of our preliminary results accurately, fairly and safely.
In the end we decided to do the ratio 25/25.
Prediction
I think that the more concentrated and smaller amount of hydrogen peroxide there is I think that there will be less oxygen released.
Equipment
- Conical flask
- Bath
- Bung and delivery tube
- 2x glass measuring cylinders
- 10ml yeast (per experiment)
- Hydrogen peroxide (amount dependent on experiment)
- Test tube
Diagram
Method
To do this experiment we will follow the method very carefully to ensure that we obtain good and accurate results.
- First we filled the bath up with water to a mark on the bath which we had previously made with a marker pen.
- We then filled a test tube with 5ml of yeast and poured it in a conical flask. We then measured in a glass cylinder the amount of hydrogen peroxide need for example 20ml.
- Then we would measure out the required amount of water for the experiment concerned for example 30ml.
- After that we then filled the collection tube up with water and placed it upside-down in the bath.
- We then put the hydrogen peroxide and the water together in the conical flask with the yeast and put the bung on securely.
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Then we made sure that the connection with the collection tube and conical flask were connected properly and measured the how long it took for the volume of oxygen to reach 50cm3 taking the reading at 10 cm3 intervals.
Safety
During the experiment we must make sure that all of the conditions that we are working in are safe and could not be of any danger to any one. This is of great importance to the experiment and others around me. To keep the experiment safe we will:
- Wear safety goggles
- Ensure any spillages are cleaned up properly
- Careful of where I put my hands while doing this experiment as the solution is a hazard
- Make sure my hair is tied back
- Make sure all of the equipment is clean before and after an experiment
- Ensure that bags and stools are safely away under the desk
Results
Averages
25H2O2 and 25H2O
Volume of O2 (cm3) 10 20 30 40 50
Time (mins) 0.07 0.12 0.16 0.22 0.27
20H2O2 and 30H2O
Volume of O2 (cm3) 10 20 30 40 50
Time (mins) 0.09 0.19 0.27 0.33 0.4
15H2O2 and 35H2O
Volume of O2 (cm3) 10 20 30 40 50
Time (mins) 0.08 0.20 0.26 0.34 0.41
10H2O2 and 40H2O
Volume of O2 (cm3) 10 20 30 40 50
Time (mins)
Volume of O2 (cm3) 10 20 30 40 50
Time (mins)
Evaluation
From my results, they tell me that my hypothesis was correct so therefore the results collected were fairly reliable. Throughout the investigation we had to measure and record the results accurately which I think was achieved to a great success.
If I was to do the experiment again I would measure the results more accurately so to ensure more specific results. I would also repeat each measurement more times so I could also gain more specific average and I would also use smaller values to get a more detailed view of my results.