• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Bubble troubel - The problem posed is how to speed up the reaction of hydrogen peroxide to water and oxygen using the enzyme catalase.

Extracts from this document...


Bubble Trouble - GCSE Coursework Raj Patel Introduction The problem posed is how to speed up the reaction of hydrogen peroxide to water and oxygen using the enzyme catalase. The catalase will be the independent variable in the experiment, and the amount of oxygen produced is the dependent variable. Using 5 different concentrations of the enzyme for the experiment we aim to measure progress by how big the foam column is to see how much oxygen is produced. I am going to vary the catalase and in order for a fair test I will keep the others constant. Hydrogen Peroxide ---...Catalase...---> Water and Oxygen Apparatus Test tube Water Bath Timer Planning the investigation I will vary the catalase in this experiment. This will be my independent variable. The dependant variables (e.g. height of foam) cannot be changed to keep this a fair test. I predict that the more catalase added to the hydrogen peroxide, the more oxygen will be produced (for the more catalase you add the more there will be to react with the hydrogen peroxide). The graph shows that the amount of catalase that was added, the more oxygen was given off. This leads me to think that the 'quantitative prediction', is true, so the amount of catalase added and the amount of oxygen given off is directly proportional. So, the more catalase molecules there are, the more chance of a reaction with the hydrogen peroxide, so therefore it is directly proportional. This is the collision theory. So, when I double the amount of catalase added, I will double the amount of oxygen produced. Inevitably, the graph will come to an end for all the oxygen molecules have been reacted with so there will be nothing else left to react which brings the end of the graph to a halt. This is due to the lock and key theory, when all the hydrogen peroxide has been reacted with, for the enzymes act as a lock and the hydrogen peroxide as a key. ...read more.


Once all of the hydrogen peroxide is broken down, there will be nothing for the catalase to react with, so this is why I predict the glass to level out. <--Lock & key--> Method Having cut 5 lots of potatoes from the same source (5 because we will have 5 different concentrations of catalase). The more potato discs the more catalase present. We're going to use 5, 10, 15, 20, 25 discs for the experiment. We added each group of discs to a group of five test tubes. Each test tube contained ph9 buffer solution. Then with another 5 test tubes containing 5ml of 20 vol hydrogen peroxide solution, we put both groups of 5 test tubes (all together 10 test tubes: 5 containing 5ml of ph9 buffer solution and different amounts of catalase, the other containing 5 ml of 20 vol hydrogen peroxide solution), and place them each in a water bath for them to equilibrate. As soon as they are all the same temperature, we spill the contents of one group of test tubes into another, and wait. After 10 minutes we measure the foam to see and differentiate between how much catalase is used and how much oxygen is produced. This is the same method that was used in our preliminary work. We kept other variables constant by the use of water baths (for the temperature to equilibrate), Results These are the results I got from the experiment. Time taken for successive 2ml of oxygen to be generated in seconds. The more slices of catalase the higher the concentration of catalase Slices 1st 2ml 2nd 2ml 3rd 2ml Average 6 79 78 80 79 8 63 65 64 64 10 49 50 49 49 12 40 39 43 41 14 25 23 26 25 Group results Slices 1st 2ml 2nd 2ml 3rd 2ml Average 6 93 77 79 83 8 63 67 70 66 10 49 56 48 51 12 42 40 45 42 14 25 27 22 25 Slices 1st ...read more.


1st 2ml 2nd 2ml 3rd 2ml Average 6 60 62 58 60 8 48 49 46 48 10 40 38 42 40 12 33 28 30 30 14 25 22 23 23 Conclusions From the tables and graphs I conclude that the higher the concentration of catalase which is added, the faster the hydrogen peroxide is broken down into water and oxygen. There is an obvious connection between the time taken and the concentration of catalase added shown in the graphs. The pink line (which is the averages of the time taken), clearly shows negative correlation when the other line shows positive correlation, so therefore it shows that the more catalase that was used the faster the hydrogen peroxide was broken down. If there had been more readings taken on the graph, eventually it would all have levelled out due to all the catalase molecules having broken down all the hydrogen peroxide molecules. This is related to collision theory. When the potato discs and the hydrogen peroxide reacts, this is where the collision theory is put into place. So with the help of the theory, I state that the more catalase added was responsible for the more water and oxygen produced, since the more catalase molecules meant that there was more potential and probability for a reaction to take place. With the lock and key theory, the more catalase there is added the more chance of one of the enzymes to lock onto a hydrogen peroxide molecule and break it down, and this is why the graph would probably level out at the end for all the catalase will break down all the hydrogen peroxide molecules and so there will be no increase in the speed of the reaction. Overall my results were pretty good, and even showed some quantative qualities, for when you double the amount of potato discs you halved the time it took for water and oxygen to be produced. The repetitions of my results give a suitable degree of accuracy. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Molecules & Cells 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 AS and A Level Molecules & Cells essays


    Water under pressure has a higher capacity to do work (like knocking over football hooligans at the end of water cannon). Pressure potential may be positive (physical pressure): water in a hosepipe has a high pressure potential. It may also be negative (tension): water being 'stretched' in a sealed syringe has a low pressure potential.

  2. Investigating the effect of the Temperature on the Enzyme Catalase when it reacts with ...

    * I cut out identical filter paper discs using a hole punch * I obtain different strength of the catalase solution in a beaker * I used forceps to dip the filter paper in the catalase solution. * I then lowered the filter paper flat onto the top of the

  1. Investigate how concentration of the enzyme catalase in celery tissue alters the rate of ...

    Repeat step 13, 26 and 14 to achieve a 5 cm3 sample of hydrogen peroxide. 47. Repeat steps 16, 18, 19 and 20, recording the results next to the "80% celery extract/catalase concentration" row and the resulting columns. 48.

  2. Biology Coursework Catalase

    I am using distilled water because it is has virtually no impurities; this of course could effect the results if it did. Test Tube Concentration of trypsin / % Volume of trypsin / cm3 Volume of distilled water / cm3 Total volume / cm3 1 0.0 0 5 5 2

  1. Reaction of Catalase and Hydrogen Peroxide

    The complex stresses chemical bonds forming a transition state. This makes the substrate more reactive. Energy is needed to form this state and the enzyme provides it. The enzyme's site of attachment and the parts that stress the substrate's bonds is known as the active site. Properties Of Enzymes 1) All are globular proteins consisting of coiled polypeptide chains.

  2. Volume of oxygen given off in the reaction between catalase and hydrogen peroxide.

    All these variables are needed to be kept constant so that the experiment is a fair test that will give me the best results possible. Pilot test A pilot test was carried out to see if any adjustments were needed before the final test was carried out to make sure I could get the best results possible.

  1. Biology GCSE Definitions

    - cannot be produced from other amino acids fat not always problem, usually large supplies protein energy malnutrition - kwashiorkor and marasmus anorexia nervosa - wasting disease, caused by intentional weight loss and bad psychological state xerophthalmia - lack in vitamin A(retinol)

  2. Investigating the break down of Hydrogen Peroxide using celery tissue to supply the enzyme ...

    This impact energy must be sufficient so that bonds can be broken within the reactant molecules and new bonds formed to produce the products. The molecules must have a proper positioning for effective collisions to occur. In this investigation the enzyme catalase is being used to break down hydrogen peroxide.

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