Concentration Affects the Rate of Oxygen Production When Raw Liver (Catalyse), and Hydrogen Peroxide Is Mixed
Preliminary Experiment (4% yeast concentration)
Hydrogen peroxide volume – 5 cm3
Water Volume -0 cm3
Concentration Volume- 20 vols
Time in Seconds Volume of O2 (cm3) Experiment 1 Experiment 2 Average
30 95 94 94.5
60 100 100 100
90 100 100 100
120 100 100 100
150 100 100 100
180 100 100 100
Modifications
The results from my preliminary experiment show that 100 cm3 of oxygen has been produced in the first 30 seconds.. This reaction is far too quick and will prevent me from analysing the effects different substrate concentrations have on enzymes if I decide to continue. I will therefore lower my yeast concentration to 1%. I will also measure the volume of oxygen produced every 15 seconds, instead of every 30 seconds. This will make my results more reliable and allow me to analyse my results to a higher degree.
Precautions
To ensure that my experiment is accurate I will:
• Keep the hydrogen peroxide in the brown bottle to stop it reacting with the sunlight.
• Try to minimise the handling of my equipment to prevent them warming up.
• Make sure that the bung has been placed correctly every time to stop oxygen escaping.
• Push the syringe in and out several times to make sure that no substance is left in the syringe.
Safety: Hydrogen peroxide is corrosive. To prevent accidents wear goggles and a laboratory coat. Also wipe up any spills immediately.
Results
Hydrogen peroxide volume – 5 cm3
Water Volume -0 cm3
Concentration Volume- 20 vols
Time in Seconds Volume of Oxygen O2 (cm3) Experiment 1 Experiment 2 Average
15 14 15 14.5
30 26 27 26.5
45 40 40 40
60 53 52 52.5
75 65 64 64.5
90 74 74 74
105 80 80 80
120 85 85 85
135 90 87 88.5
150 92 90 91
165 94 93 93.5
180 94 94 94
195 96 94 95
210 96 94 95
Hydrogen peroxide volume – 4 cm3
Water Volume -1 cm3
Concentration Volume- 16 vols
Time in Seconds Volume of Oxygen O2 (cm3) Experiment 1 Experiment 2 Average
15 11 18 14.5
30 22 24 23
45 30 33 31.5
60 38
Hydrogen peroxide volume – 5 cm3
Water Volume -0 cm3
Concentration Volume- 20 vols
Time in Seconds Volume of O2 (cm3) Experiment 1 Experiment 2 Average
30 95 94 94.5
60 100 100 100
90 100 100 100
120 100 100 100
150 100 100 100
180 100 100 100
Modifications
The results from my preliminary experiment show that 100 cm3 of oxygen has been produced in the first 30 seconds.. This reaction is far too quick and will prevent me from analysing the effects different substrate concentrations have on enzymes if I decide to continue. I will therefore lower my yeast concentration to 1%. I will also measure the volume of oxygen produced every 15 seconds, instead of every 30 seconds. This will make my results more reliable and allow me to analyse my results to a higher degree.
Precautions
To ensure that my experiment is accurate I will:
• Keep the hydrogen peroxide in the brown bottle to stop it reacting with the sunlight.
• Try to minimise the handling of my equipment to prevent them warming up.
• Make sure that the bung has been placed correctly every time to stop oxygen escaping.
• Push the syringe in and out several times to make sure that no substance is left in the syringe.
Safety: Hydrogen peroxide is corrosive. To prevent accidents wear goggles and a laboratory coat. Also wipe up any spills immediately.
Results
Hydrogen peroxide volume – 5 cm3
Water Volume -0 cm3
Concentration Volume- 20 vols
Time in Seconds Volume of Oxygen O2 (cm3) Experiment 1 Experiment 2 Average
15 14 15 14.5
30 26 27 26.5
45 40 40 40
60 53 52 52.5
75 65 64 64.5
90 74 74 74
105 80 80 80
120 85 85 85
135 90 87 88.5
150 92 90 91
165 94 93 93.5
180 94 94 94
195 96 94 95
210 96 94 95
Hydrogen peroxide volume – 4 cm3
Water Volume -1 cm3
Concentration Volume- 16 vols
Time in Seconds Volume of Oxygen O2 (cm3) Experiment 1 Experiment 2 Average
15 11 18 14.5
30 22 24 23
45 30 33 31.5
60 38