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The aim of my experiment is to determine how temperature affects the rate of lipid digestion by lipase.

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G.C.S.E SCIENCE COURSEWORK. The aim of my experiment is to determine how temperature affects the rate of lipid digestion by lipase. Preliminary experiment Quantities: * 3 centimetre cubed of milk. * 5 drops of phenolphthalein. * 3 centimetre cubed of sodium carbonate (alkaline). * 1 centimetre cubed of lipase. Must be added last. My preliminary experiment was extremely essential as it helped me to find out what quantities I shall have to use in the main experiments that was 3 cm of sodium carbonate as shown above. It also gave me a rough outline of how the main experiment would work out. What I am going to do. METHOD: * Set up a water bath as the one shown in the above diagram. * Then heat water bath to a desired temperature which are (20,30,40,50,60 C) preferably begin with 20 and work to 60. * Next you have to add 3 cm of milk, 5 drops of phenolphthalein and cm of sodium carbonate to the test tube. Measurements must be precise. * You must then stir the mixture if completed successfully mixture will transform to a pink colour. ...read more.


If I were to change these quantities then I would be creating a fault, which would be noticeable on my graph and results. If I maintain the same quantities it would show the reaction changing as the temperature does yet it would still fit the pattern. The factor I am deliberately changing is the desired temperature (variables). The ranges of values I will be required to use for the factor I am varying are 20,30,40,50 and 60 C. We will carry out the experiment all these different values. I will ensure my results are reliable by repeating the experiment three times for each of the above temperatures. This will enlarge my chances of accomplishing a fair test I will also be able to calculate an average for each temperature. Once we had stirred the mixture at all the different temperatures the mixture transformed from pink to white. The reason for this is that it creates an acid after the reaction happens which is shown by the phenolphthalein in the mixture. My conclusion. My results clearly show that lipid digestions by lipase rates are affected by temperature. ...read more.


One of my results did not fit the general pattern this was 40C. It was not explainable and was the anomaly that occurred in my experiment. 40 C was an anomalous as it did not fit the curved line of best fit on the graph shown on the previous page. However it is still accepted because it fits the general trend. At first we thought something had gone wrong but we had received the same outcome after two more attempts. The reason for this could possibly be that we did not add the precise measurement of quantities. I am confident about my conclusion, as I now certainly know that temperature does affect the rate of reaction. Furthermore I have also backed my conclusion up by stating the maximum temperature is just above 60C. I can improve the reliability of this experiment by doing repeating it several more times for each temperature and then perhaps I would receive a more accurate average. To obtain further evidence I could have changed the variables, I could have had more results by increasing the temperature by 5 C each time instead of 10 C this would have given me a more precise average ...read more.

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