The Effect of Concentration of the Catalase Research Question: Does the concentration of liquid catalase affect the amount of oxygen gas produced?Rationale Many variables can be implemented to increase the rate of a chemical reaction. The presence of an enzyme can be used to help aid in increasing the rate of reaction. The type of enzyme being investigated is the catalase in its liquid form. The purpose of the liquid catalase of any enzyme is when it reacts with hydrogen peroxide it produces oxygen gas and water.
H2O2+Catalase’H2O+O2 The concentration of an enzyme can be adjusted by diluting the catalase by using water. Diluting the concentration of the enzyme will decrease the rate of oxygen gas produced in the reaction this is due to the solubility level of the enzyme will decrease resulting in more of the reactants as there is less of the catalase to react with the hydrogen peroxide, decreasing the amount of oxygen gas produced.
Original MethodThe original experiment that was obtained from the Pearson Biology Unit 1 and 2 textbookModifications to the original MethodRefinementsThe refinements that were made to the original method to the following:Using a liquid catalase- Changing the catalase from liver to liquid catalase creates validity with the data as the amount of catalase can be measured accurately.The use of a oxygen sensor- To determine how much oxygen was produced during the experiment as gas pressure wouldn’t give an accurate reading. So a oxygen sensor was used, this way the only gas that was measured was the oxygen and would only collect data for the amount of oxygen.ExtensionsThe use of different concentrations- extending the experiment to incorporate a variety of dilutions to the experiment will allow the data to be compare and determine the relationship of the concentration of the catalase and the amount of oxygen produced , improving the reliability of the data collected. Conducting multiple trials- Extending the experiment to create 3 trials adds significant reliability and validate the recordings. This is due to anomalies can be identified and eliminated depending on how inaccurate it might be.Risk AssessmentReferenced the MSDS forms in risk assessHydrogen peroxide can cause eye irritation- were glasses to protect eyesSpillage of the hydrogen peroxide, water and catalase can occur- keep objects in a safe and secure areaMeasuring the catalase and hydrogen peroxide- when measuring these 2 substances they need to be indifferent cylinders otherwise they will react with any left over of the other substance, causing inaccuracy and creating false data.Raw DataThe following data was collected during the experiment:Concentration of Catalase Oxygen Gas Produced (%)Catalase:H20 Ratio (ml) Trial 1 Trial 2 Trial 31:03 29.5 29.16 32.421:06 28.63 28.55 31.131:12 26.39 27.17 28.271:24 23.34 22.77 26.621:48 19.26 20.56 22.43Processed DataWhen calculating the data, the following deemed to be appropriate:Using the mean was the most accurate when finding the averageThe standard error was then calculated for one of the dilutions and this was then used to determine how much give way’ there is when the experiment was conductedCalculation ExampleMean of Oxygen gas produced For the ratio of 1:3 Trial 1 + Trial 2 + Trial 3/ number of Trials29.5+29.16+32.42= 91.08/3 Mean = 30.36Measurement Deviation Mean- Individual measurement30.36-29.5=1.130.36-29.16=1.4430.36-32.42=-1.82Square each of the deviations(makes any negative, positives) 1.12=1.211.442=2.0736(-1.82)2=3.3124The sum of the deviations 1.21+2.0736+3.3124=6.596Sum is then divided by one less than the sample size (n-1). 6.596·2=3.298The square root of the number found above is taken to provide the standard deviation 3.298=1.816The standard deviation is then divided by the square root of the sample space (n) to provide the standard error 1.816€3=1.048Table 1: Results of the 3 Trials including the average & Standard Error Concentration of Catalase Oxygen Gas Produced (%) Average amount of Oxygen Gas Produced (%) Standard error for the Average amount of oxygen produced (%)Catalase:H20 Ratio (ml) Trial 1 Trial 2 Trial 3 1:3 29.5 29.16 32.42 30.36 ±1.0481:6 28.63 28.55 31.13 29.44 ±0.8471:12 26.39 27.17 28.27 27.28 ±0.5451:24 23.34 22.77 26.62 24.24 ±1.2001:48 19.26 20.56 22.43 20.75 ±0.920 InterpretationThe data shows that the mean for the amount of oxygen produced has a standard error. The standard error will show a range where the true value may range. The data demonstrates as the concentration of the catalase decreases the amount of oxygen gas produced is increase. The average was then determined for each of the concentration AnalysisThe maximum standard error across all of the averages was ±1.200 and the minimum amount of standard across all the averages was ±.545. The greater standard average you indicate some uncertainty and inaccurate results from the data, this can be a reason for incorrect measurement of the concentration or amount of hydrogen peroxide used to react with. However the uncertainty’s that have been calculated are no greater than 2%. This demonstrates that the experiment that was conducted has validity due to the standard area not being an extreme range for the amount that was found to range.Graph 1: All 3 trials and the Average amount of Oxygen gas produced left180975Interpretation:The data above shows the amount of oxygen produced with the different concentrations of catalase. As the concentrations are lowered it is evident in the graph above that the amount of oxygen being produced is decreasing as the concentration is being lowered. It can also be identified that trial 3 has a higher production of oxygen but still follows the trend of it decreasing as the concentrations lower. This assumption can be made by the effects dilution has on a catalase. When A catalase has been diluted the solubility level of the catalase has increased making the reaction occur of a longer period of time and a slower rate. All of the trials demonstrate a decreasing rate, this implies that the concentration level of the catalase has a negative effect on the oxygen gas produced. Analysis: The graph demonstrates how much oxygen is produced when using different types of concentrations of catalase. In the first trial it is shown that the concentration to produce the largest amount of oxygen was 1:03. This then became the case for the next 2 trials producing between approx.. 29-32.5% oxygen gas. Compared to the lowest concentration (1:48) in trial 1 producing 19.16% oxygen gas and for the following two more trials producing 20.56% and 22.43%. In the graph the different trials can be shown overlapping each other, this helps prove reliability due to the figures being close. How ever this may not be the case with the true values of the data as standard error can be identified with results. Hence why the data will range within the standard error that was calculated for the average of each trial.Graph 2: The average amount of Oxygen ProducedInterpretation The graph above demonstrates the average of 3 trials using a range of dilutions. The trend is identified as the dilution increases the amount of oxygen gas produced decreases. The graph also demonstrates errors bars that have been calculated. The error bars has been used to indicate how far the data that was collected can be off the true value.Analysis The error bars in the graph show that the data has a possibility of the data increasing and not supporting the original data. The error bars are shown to be overlapping at every concentration level. This suggests that concentration before and after a dilution falls in the same range.EvaluationLimitations that were faced during the experiment include inaccurate measurement when measuring the catalase, hydrogen peroxide or distilled water. This can be caused due to an incorrect eye measurement being made when using the measuring cylinder. This then creates standard error for the measurements that may not apply to the measurement. When placing the gas sensor over the conical flask it would’ve have not been place on top at the very beginning, which implies oxygen wouldn’t have been measured creating a false reading on the data logger. The time frame that was used on the data logger will limit the amount of oxygen to be measured. The maximum amount of time the data logger tracks is up to 5mins then stops the recorded. This affects the measurement of the highly diluted as the reaction takes longer to take place ending it at it 5 minutes will stop the data to keep on increase.When commencing the practice trial, it was demonstrated that the catalase was limiting in the reaction. It was shown as all the concentrations produced the same amount of oxygen being produced. Sources of errorSolutions to resolve and minimise these sources of errors that were found in the experiment consist of once the reaction has no increasing rate for the production of oxygen gas the experiment will end. This will limit any oxygen getting into the flask that it not form the reaction and help create less uncertainty in the data.Another resolution to help create less uncertainty in the data is to double check the ratio of water to catalase being used with the reaction. When the hydrogen peroxide is limiting in the reacting not all of the catalase is being used within the reaction, creating data that will be the same throughout the data. When the catalase becomes the limiting substance in the reaction the results will vary throughout each concentration. This is due to the hydrogen peroxide producing the oxygen gas. When all of the hydrogen peroxide isn’t limiting in the reaction then there will hydrogen peroxide will remain in the flask.Suggested ImprovementsThe improvements that can be used to help minimise the amount of standard error are to use pipette to pour the hydrogen peroxide into the conical flask. By doing this is allows less time for the oxygen sensor to be put over the flask, due to the small size of the pipette. This stops any of the oxygen gas being produced to escape. To increase the accuracy of the findings for each of the types of concentrations, more trials can be conducted. By doing more trials this allows for any invalid data to be used in the calculations. When recording the data, instead of only recording the optimal amount of oxygen gas produced the time that it was recorded at could have been recorded. Including the time taken to reach the highest point will aid in demonstrating that the rate of reaction would have increased.ConclusionIn conclusion, it is evident that the concentration of the catalase will effect the rate of reaction. The highest concentration of the catalase has been shown to produce the highest amount of oxygen. The concentration that produced the smallest amount of oxygen had demonstrated to be the ratio 1:48. However more trials would have to be done to ensure accuracy and validity of the date that was found during the experiment.AppendixMean of Oxygen gas produced For the ratio of 1:6 Trial 1 + Trial 2 + Trial 3/ number of Trials28.63+28.55+31.13= 88.31/3 Mean = 29.43Measurement Deviation Mean- Individual measurement29.43-28.63=0.8129.43-28.55=0.8929,43-31.13=-1.69Square each of the deviations(makes any negative, positives) 0.812=0.650.892=0.79(-1.69)2=2.86The sum of the deviations 0.65+0.79+2.86=4.3Sum is then divided by one less than the sample size (n-1). 4.3·2=2.15The square root of the number found above is taken to provide the standard deviation 2.15=1.466The standard deviation is then divided by the square root of the sample space (n) to provide the standard error 1.466€3=0.847BIBLIOGRAPHYEffects of Dilution