APPARATUS
- Water bath
- Crushed ice
- Thermometer
- Screw clip
- Stop clock
- Beaker
- Delivery tube with bungs to fit the test tubes/boiling tubes
- Hydrogen peroxide
- Soaked peas
-
10cm3 syringe barrel
- Test tubes or boiling tubes
- 10ml Measuring cylinders
- Distilled water
VARIABLES
In this experiment the DEPENDENT VARIABLE is going to be the temperature while the INDEPENDENT VARIABLE is going to be the amount of oxygen gas collected.
I will use 4 crushed peas of the same/similar size for all the investigation. I will also make sure that I use 4cm3 of hydrogen peroxide and 2cm3 of distilled water to make it a fair test.
SAFETY PRECAUSIONS
- To wear safety goggles to protect your eyes from the vapour from the hydrogen peroxide as it is an irritant.
- To handle the glassware with care making sure nothing will break as they are very fragile.
PROCEDURE
-
Crush 4 peas of the similar size and add 2cm3 of water to it and pour the crushed peas into the boiling tube.
- Put the boiling tube in the water bath with crushed ice as shown in the diagram below.
-
Then open the cock of the boiling tube and add the 4cm3 of the hydrogen peroxide to the crushed peas that is in the boiling tube and close it quickly.
- Start timing for 2 minutes once you see the first bubble entering the syringe and measure the amount of oxygen collected
NOTE: - take the reading of the syringe barrel before and after the hydrogen peroxide is added.
Amount of oxygen collected = after 2 minutes reading - before reading
- Repeat the experiment at different temperatures (but without the crushed ice) and record the amount of gas collected.
DIAGRAM
RESULTS
Graph enclosed at the end
ANALYSIS
The amount of oxygen collected increased with the temperature only till 390C i.e. the optimum temperature. This is clearly shown in my results
The anomalous result that I have highlighted on the results table and marked on the graph comes from the 250C. This is because the curve on the graph does not pass through this point.
The anomalous result must have occurred due to an error during the investigation. It could have been the reading error when reading the amount of oxygen after the hydrogen peroxide is added. It could also have been that the temperature was not exactly 250C.
EVALUATION
The result I got from my investigation clearly show that the as temperature increases the amount of oxygen produced also increases but only to about 390C, after which the amount of oxygen being collected starts to decrease. The results seem to be reliable from my graph apart from that of 250C. I took 3 readings for each temperature and calculated the mean to make my results more reliable.
CONCLUSION
I would conclude by saying from my experiment that my hypothesis is correct and agree that more gas is produced with increasing temperature only until the optimum level (390C) after which the amount of gas produced starts to decrease.