Part A
Hypothesis: The larger the amount or mass of the catalyst (manganese oxide) used, the faster the rate of reaction because the speed of the catalyst increases. From my experiment the more catalysts used the more hydrogen peroxide splits up to create oxygen at a faster rate.
Equipment:
Manganese (IV) oxide – The catalyst used to test the hypothesis.
Conical flask – Used to contain the hydrogen peroxide and manganese (IV) oxide .
Timer – To time how long it takes for the water to come out of the tube due to oxygen entering.
Hydrogen peroxide – The solution used to test the hypothesis.
Bung – Used to stop gas escaping from the flask.
Delivery tube – To collect the oxygen that was produced.
Water trough – To collect oxygen over water.
Weighing boat – To hold the manganese (IV) oxide while weighing.
Weighing scale – to hold the manganese (IV) oxide to make it accurate when out how much we are using.
Measuring cylinder – To measure out the hydrogen peroxide used.
Black card – To keep the hydrogen peroxide away from any form of sunlight and normal light.
Boiling tube – To store the solutions.
Controls: The independent variable is the mass of the manganese (IV) oxide used each time. The dependant variable is how quickly the oxygen was produced (in seconds).
Control variables:
The volume of hydrogen peroxide used was kept the same throughout the whole experiment and was kept 20cm3 in the measuring tube. We kept the hydrogen peroxide the same to ensure that we only tested the mass of the catalyst. If we use different amounts of hydrogen the test will become unfair and the different amounts make the reaction to occur quicker.
Keep the concentration of the hydrogen peroxide the same as we only wanted to test the catalyst rate and not affect any other factors. If we changed the concentration of the hydrogen peroxide the speed of the reaction will increase.
Keep the same boiling tube, other boiling tubes have different shape and size and may hold a different volume of solution within it.
Keep the same temperature of the room, so it does not interrupt the experiment and change the rate of the reaction
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Method:
1. I set up the apparatus
2. I poured 20cm3 volume of hydrogen peroxide solution into the conical flask]
3. I added 0.1g of manganese (IV) oxide to the solution
4. I quickly put the bung into the conical flask, place the delivery tube under the boiling tube and start the timer
5. I stopped the timer when the boiling tube was full of gas
6. I then repeated steps 2 and 5 with other masses of manganese (IV) oxide up to 0.5g.
Overall Plan:
1. I measured the catalyst three times (0.1g, 0.2g, 0.3g, 0.4g, 0.5g) in a weighing scale.
2. I set up the equipment with a bee hive shelf in a water trough. The conical flask was connected to a bung and the delivery tube to collect the oxygen produced using a boiling tube.
3. I measured (20ml) of the hydrogen peroxide using a measuring cylinder.
4. I poured it into the conical flask and added the different masses of the catalyst.
5. I timed how long the oxygen filled the boiling tube using the different masses of the catalyst.
6. I repeated my experiment three times and found the average
7. My method tested my hypothesis because the time for the oxygen to fill the boiling tube decreased as the mass of the catalyst increased.
8. I used catalyst of masses
