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

Investigation into the decomposition of hydrogen peroxide.

Extracts from this document...


Biology Coursework-Investigating into the decomposition of hydrogen peroxide. Introduction I am investigating into how a certain factor alters the rate of decomposition in hydrogen peroxide. When yeast is mixed with hydrogen peroxide, bubbles of oxygen are produced. This is because hydrogen peroxide has been broken down into water and oxygen through a chemical reaction known as decomposition. The equation for this is: Hydrogen peroxide water and oxygen 2H2 O2 2H2O+O2 The rate of the reaction is determined by the enzyme in the yeast, catalase. This is an enzyme, which acts like a catalyst i.e. it speeds up what happens in the reaction; it is never used up in a reaction. In order to measure the speed of the reaction you apply the data to this formula: Speed of reaction=amount of oxygen made/time. Variables: * Temperature, * Concentration of enzymes, * Level of hydrogen peroxide. I will provide a brief explanation into each of the variables below: Temperature This variable will affect the rate of decomposition because, as the catalase enzymes in the yeast are heated, the molecules move around more, and collide into one another. Consequently, the hydrogen peroxide begins to decompose quicker. However, if you heat the enzymes beyond a certain point, the rate of decomposition in the hydrogen peroxide will slow to a halt. ...read more.


Method I will use the apparatus listed above in order to carry out my experiment. Firstly, I will prepare myself for the experiment so that I will be safe. I will tie my hair back, make sure there are no hazards around the workplace such as bags or stools and then I will put on my safety goggles. Then, I will proceed to set up my equipment by fixing up the sand and clasping the gas chamber and the separator in it. The separator is used so that no liquid will get inside the gas chamber, as the syringe would then stick and the results would be unreliable. I will then connect the separator to the bung which I will place in to my test tubes when carrying out the experiment. Then I will use the different measurements of yeast and hydrogen peroxide and place these into the test tube whilst quickly putting the bung in and starting the stopclock. The measurements I will use are from 1-10cm3.I I will then taking a reading off the gas chamber after a number of 10 second intervals i.e. at 10,20 and 30 seconds. However, in my pilot tests I will only collect my results after 30seconds. ...read more.


So, because the data all has quite strong positive correlation, this shows that the amount of oxygen produced is directly proportional to the amount of yeast enzymes. However, in every graph I can see that the very first result I took was considerably lower than the rest of the results. Each graph has this result as its single anomalous result. This anomaly was most likely to have been caused by a piece of the equipment. Perhaps it was the syringe that took a while to start moving, this could have been caused by a small amount of water getting trapped in the syringe making it stick. The only other thing in my method that could have caused unreliable or inaccurate data could be the fact that the timing of the experiment could not be absolutely accurate as I was using a stopclock to manually time it myself. Although, allowing for human error, I feel that my results, as shown, are overall very accurate. In order to improve my method in future I could use a data logger to time my results as this would be able to take a number of consistent more accurate readings. My graphs are clear and obvious, and give sufficient evidence to support my conclusion and prediction as everything in my method went as planned and I produced a set of plausible, accurate results. Biology Coursework Lauren Richardson 11G ...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. Investigate the factors, which affect the rate of decomposition of Hydrogen Peroxide.

    It was too fast. exploded 10 1g 60 Too fast 10 1g 20 Too fast 10 0.5g 80 Too fast 10 0.5g 60 3 secs 10 0.5g 20 7.67 secs 5 0.5g 80 Too fast 5 0.5g 60 6.45 5 0.5g 20 17.30 My preliminary results were very useful.

  2. Factors Affecting the Rate of Catalytic Decomposition of Hydrogen Peroxide.

    Range of Results I have decided that the suitable range of results for the main investigation will be to take an increment of 2 Vol. from 4 Vol. to 20 Vol., leaving us with 9 points to be plotted on the graph.

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

    * Spillages must immediately be cleaned up in the case of slipping on it or touching it mistakenly. * Hair should be pulled back to avoid chances of having it dipped in chemical substances. It can also interfere with chemical reactions.

  2. Investigation into the effect of substrate concentration on the rate of hydrogen peroxide decomposition ...

    optimum, a temperature closer to room temperature will be much easier to keep constant. If the solution of H2O2 is allowed to equilibrate with the room temperature of ~25oC before being used, a constant starting temperature can be achieved. A water bath of room temperature will also be used to maintain the temperature through out the reaction.

  1. The effect of concentration on the activity of catalase.

    Pectinase then becomes inactive. Pilot Experiment Aim: To investigate the effect of varying the concentration of the enzyme catalase, on the rate of reaction. The volume of oxygen produced per unit of time will be measured as an indication of the rate of reaction.

  2. Effect Of Substrate Concentration On The Activity Of Catalase

    nearest 0.1 second even though the stopwatch shows the measurements to the nearest 0.01 second. ANOMOLIES The plotted results on the graph produce a straight line of best fit to begin with which then goes into a curve of steadily decreasing gradient.

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

    The idea that a substrate fits into the active site of an enzyme is called the 'lock and key' theory. As there is no inhibitor present I can presume that there will be nothing to obstruct the enzymes active site, as inhibitors, whether permanent or temporary, can slow a reaction

  2. The Decomposition of Hydrogen peroxide - investigation in to the effect of concentration ...

    * Concentration - Increasing the concentration of a reactant also increases the speed of a reaction because there are more particles in the same volume. Lower concentration higher concentration The more crowded the particles the more collisions will occur( and therefore the more effective collisions)

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