• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10

Investigate how temperature affects the rate of reaction of the enzyme catalase on its substrate hydrogen peroxide.

Extracts from this document...


Aim To investigate how temperature affects the rate of reaction of the enzyme catalase on its substrate hydrogen peroxide. Scientific Background Enzymes are biological catalysts which increase the rate of reactions by lowering the activation energy needed for the reaction to tale place. The activation energy is the amount of energy needed for molecules to react when they collide. Molecules need to collide in order to react, this is known as the collision theory. When they collide they may not react as a certain amount of energy is required to break bonds, this energy is the activation energy. Enzymes are made of a long amino acid chain, within this some molecules are attracted to each other, so the chain folds in on itself to form a 3D shape. How enzymes are shaped. An area on the surface of the enzyme is known as the active site. This is where reactions take place to form or break down substances. Enzymes are specific which means a particular enzyme only works on one substance known as its substrate. For example, the substrate of amylase is starch and the substrate of lipase is fats. They only have one substrate because the active site is formed in a different shape for each enzyme, where only one substance can fit. The 'lock and key' hypothesis states that the enzyme is like a lock which will only have one key. 'Lock and Key' hypothesis The substrate shown is the only substance that fits the enzyme. An enzyme substrate complex is the compound formed when the substrate is attached to the active site, it is only in this form for a short time while the substrate is being broken down. ...read more.


Using the same potato, as different potatoes will have different levels of catalase present, ? Using the same concentration of hydrogen peroxide, ? Using the same cork borer to cut the potato, to keep the surface area constant. The experiment will be safe by: ? Always wearing safety goggles, as hydrogen peroxide an damage your eyes, ? Not spilling the hydrogen peroxide as it is an irritant, and bleaches, ? Taking care when cutting the potato, ? Taking care when handling hot water. Results The results obtained are as follows: There was not enough time to conduct two repetitions, however, one repetition was conducted. The rest of the method was followed as planned. 1st Set of Results Gas collected (ml) with the following temperatures (?C) Time (s) 10 20 30 40 50 60 70 30 0.05 0.10 0.20 0.40 0.10 0.10 0.20 60 0.10 0.10 0.40 0.80 0.20 0.20 0.30 90 0.10 0.20 0.60 1.30 0.30 0.40 0.30 120 0.20 0.50 0.90 1.80 0.40 0.40 0.30 150 0.20 0.50 1.10 2.20 0.40 0.40 0.30 180 0.25 0.60 1.40 2.70 0.40 0.40 0.30 210 0.30 0.70 1.60 3.00 0.60 0.40 0.30 240 0.30 0.80 1.80 3.40 0.60 0.40 0.30 2nd Set of Results Gas collected with (ml) the following temperatures (?C) Time (s) 10 20 30 40 50 60 70 30 0.05 0.05 0.10 0.20 0.30 0.30 0.25 60 0.05 0.05 0.20 0.60 0.35 0.40 0.25 90 0.20 0.10 0.30 0.90 0.40 0.40 0.25 120 0.10 0.20 0.60 1.30 0.45 0.40 0.25 150 0.15 0.40 0.80 1.80 0.45 0.40 0.25 180 0.20 0.45 1.00 2.20 0.45 0.40 0.25 210 0.20 0.60 1.30 2.70 0.45 0.40 0.25 240 0.30 0.70 1.60 3.00 0.45 0.40 0.25 Averages Gas collected (ml) with the following temperatures (?C) Time (s) ...read more.


Hot and cold water were mixed to achieve accurate temperatures. An anomalous results occurred during the repeat reading of the 10?C experiment, the reading at 90 seconds is higher than that at 120 seconds. This reading was ignored when taking the average so It does not affect the analysis. It occurred because the measurement was misread, it may have been 0.1 cm3, instead of 0.2 cm3. Another anomalous result occurred during the first taking of the 50?C experiment, gas was released at 210 seconds when the experiment seemed to have stopped. The gas may have been trapped in the delivery tube and should have been released earlier in the experiment. This was taken into account when drawing the best fit line on the graph, so does not affect the analysis. The method used was good enough to achieve reliable readings , but it can be improved by measuring the mass of the gas lost, this would be more accurate as digital readings would be taken. Using a smaller frequency and a larger range of temperatures would give more evidence for the conclusion. However would require more time and equipment. Other improvements are, using thinner measuring cylinders, to measure out the hydrogen peroxide and the gas produced. Using a thermocouple thermometer to accurately measure the temperature. The hydrogen peroxide took time to heat up as the test tube is glass and is insulated. Using a better material would save time and would have allowed the plan to be completed. Using electronic equipment to take readings a exactly 30 seconds, would eliminate human error. Further work that would extend the investigation and give more evidence to the conclusion would be, to use different concentrations of hydrogen peroxide and lengths of potato, to see how these affect the rate of reaction. Using other substances with catalase, like liver, to see how enzyme concentration affects the rate. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Patterns of Behaviour essays

  1. The Effect of Catalase in the Breakdown of Hydrogen Peroxide

    10. (Have a stopper attached to the delivery tub in hand and be ready to press the stop watch) pour 5ml of the hydrogen peroxide into the conical flask and straight away close the top with the stopper. 11. Immediately activate the stop watch.

  2. Free essay

    Close Your Eyes

    "Well, the kiss, I'm not exactly an expert." She kept going on about how she was scared and didn't want me to be put off. Someone was knocking at the front door and I could see Dougie wasn't going to answer it. He was too busy cleaning up the Nachos and smashed glass that was on the floor.

  1. How temperature affects the rate at which bread dough rises and find out the ...

    This contains enzymes carrying out the reaction of fermentation. It means it produces CO2, which is a gas that expands. Ethanol is also produced. For these products to form the glucose must break down into C02, Hydrogen and oxygen then rejoin to form Ethanol. This is why the dough rises and the temperature has a crucial effect on this

  2. Enzymes - show how substrate concentration affects the rate of reaction for an enzyme ...

    made due to the equipment used, so I could change the equipment in order to get more accurate and reliable results. The preliminary helped me identify the areas in which errors were made and gave me a chance to improve the method to lower the number of errors.

  1. Investigation On The Enzyme Trypsin

    the wrong percentage or pH of trypsin, or I made a mistake when filling my beaker with trypsin. I certainly think that there was some kind of mistake made on that day, and I think that explains the anomaly. I also had some difficulty with telling when the entire gelatin had been denatured.


    Figure 3: the structure of a saturated and unsaturated fatty acid. Sodium carbonate Sodium carbonate is used to reduce the acidity of chemicals, it is therefore maintains a very high pH which provides its alkali features. The sodium carbonate may be added to milk, before bile salt is in contact

  1. Investigation into the initial rate of hydrogen peroxide decomposition when the enzyme catalase is ...

    Needed because it is the variable in the investigation. Boiling tubes 15 Where the reaction will take place. Need 15 as each experiment will be carried out 3 times Water bath 2 One to keep a constant temperature in the boiling tubes and one to help trap O2 given off Measuring Cylinder(s)

  2. The action of catalase on hydrogen peroxide.

    can be obtained. The relationship between substrate concentration and rate of reaction is described by the Michaelis-Menton equation: v = Vmax [S] Km + [S] Vmax is a measure of the maximum rate at which an enzyme can act, and it is the horizontal asymptote of the graph of substrate

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work