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

The effect of temperature on the production rate of carbon dioxide in yeast.

Extracts from this document...

Introduction

BIOLOGY COURSEWORK The effect of temperature on the production rate of carbon dioxide in yeast. Introduction: We are using yeast balls to work out what affects the production of carbon dioxide. The reaction to be studied is as follows: C6H12O6 C2H5OH + 2CO2 (+ 2 ATP) There are four factors which affect the reaction rates : surface area, use of catalyst, concentration and temperature. It is impossible to vary the surface area , as if the yeast balls were chopped up into small pieces, then the yeast inside would die, and so no reaction would occur. The use of catalysts is a hit-and-miss variable, as it is basically putting in random chemicals and seeing if they react. Both temperature and concentration are suitable for variation, but I have decided to change the temperature, as I do not think that varying concentration (i.e. amount of yeast balls), would be that effective. ...read more.

Middle

Increased temperature means an increase in kinetic energy of the molecule, hence a greater reactivity. Hypotheses: The higher the temperature of the reaction, the faster the reaction rate. I believe that this will be true until about 70 oC, at which point the yeast cells shall start to denature. This means that it will affect the upper values. Key: - HCl molecule - yeast cell There is the same amount of acid and yeast in both container (i) and (ii), but container (ii) has a higher reacting temperature. Therefore, it speeds up the random motion of molecules and the yeast cells will have much more energy and therefore, collide quicker and with more force. This means that the reaction will occur much quicker. As the temperature increases, the time taken for 1cm3 of CO2 to be produced decreases, meaning the reaction rate is faster. And as the values for the reaction rate are directly proportional to 1/t (or indirectly proportional to t), I have drawn up the above hypotheses graphs. ...read more.

Conclusion

So, I have therefore decided to see how long it takes to make x cm3 carbon dioxide. Now I have to decide how much CO2 am I looking to collect for the experiment. Having said that at low temperatures, the reaction rate is very slow, I have decided to see how long it takes for 1cm3 to be collected. Also, to ensure that the experiment was correct, I set up another one, where instead of collecting the CO2, I bubbled it through HCIS solution, to ensure that it was in fact carbon dioxide. This proved positive. The results are as follows: Temp (oC) 40 50 60 70 80 90 Time to collect 1cm3 (s) 1733 1652 1138 1100 1078 784 These results are not as I predicted, and so I can see that I have either made an error, or my hypothesis was wrong. However, after talking to the rest of the class, I have decided that the yeast must have been a bad batch, because nobody really got good results. ...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. Rates of reactivity.

    similar as possible throughout the experiment and hopefully be a fair test with the results in direct relationship to each other. If these varied then I would expect the result to be inaccurate and so ruin my experiment. Prediction It is believed that the increase in the surface area of

  2. Null hypothesis:The type of sugar will have no effect on the rate of respiration ...

    Galactose is found in dairy products but also synthesised by the body to form part of glycolipids and glycoproteins. Galactose is not particularly water soluble. Maltose is the least common disaccharide; it is a reducing sugar and is forms on the partial hydrolysis of starch.

  1. To investigate the effect of varying the masses of white sugar and yeast and ...

    The 75,000mg of flour was then quantitatively added to the yeast/sugar solution and thoroughly mixed with a glass stirring rod until a semi-liquid dough or slurry was formed. This slurry was carefully poured into a 100ml measuring cylinder till it's top reached the 30ml mark.

  2. Free essay

    Close Your Eyes

    I wondered if maybe Carrie had been wrong about him liking me and he did only want my opinion on his new song but I prayed that she was right and that he wanted something more. I spent ages trying to figure out what to wear but eventually I decided

  1. Haber Process for the Production of Ammonia

    and N2 (g) and less NH3 (g). Reversible Reactions 1. The reaction of nitrogen and hydrogen is a reversible reaction meaning the reaction can proceed in either forward or the reverse direction depending on conditions. 2. The forward reaction is exothermic reaction (produces heat)

  2. Determine the effect temperature has on the rate of reaction.

    * Repeat the above using ethanoic acid. Therefore the results can be compared; a weak acid versus a stronger acid. Method 1 involves measuring the initial rate. The time taken has to be measured to collect 20cc and 40cc of hydrogen gas for a 1M solution of HCl and ethanoic acid.

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