• 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 Vitamin C Content of Lemon Juice

Extracts from this document...

Introduction

Biology IA The Effect of Temperature on the Vitamin C Content of Lemon Juice 2013 Design Aim To investigate the effect of changing temperature on the Vitamin C content of lemon juice Research Question How does changing temperature the temperature of lemon juice effect its Vitamin C content? Variables Independent Variable – Temperature of Lemon Juice (°C) Dependant Variable Vitamin C content as measured by the number of drops taken to turn the DCPIP solution colourless Results Raw Data Table showing the effect of changing temperature on the Vitamin C content of lemon juice shown by the number of drops of lemon juice required to turn DCPIP colourless. Temperature of the lemon juice (°C) ±1 Number of drops of lemon juice required to turn DCPIP colourless Observations Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 20 3 3 2 3 3 The juice quickly went pink then colourless. 30 8 8 7 7 6 The juice quickly went pink then colourless. 40 10 10 10 9 9 The lemon juice went pink then colourless. 50 14 13 12 12 11 The juice slowly went pink then colourless. 60 20 18 16 10 16 The juice slowly went pink then colourless. Processed Data Table showing the effect of changing temperature on the Vitamin C content of lemon juice shown by the number of drops of lemon juice required to turn DCPIP colourless Temperature of the lemon juice (°C) ...read more.

Middle

This result would have greatly lowered my mean, if I ignore the value from the fourth trial the mean for 60°C increases to 17.5 instead of 16 so my results are not as accurate. The consistency of my other results means I can assume that this outlier was due to systematic errors. My results are reflected by these other experiments such as the one a found online which directly measured the concentration of vitamin C in different fruit juices at varying temperatures. Their results are shown in the table below. The findings were very similar to my own, as the temperature increases the vitamin C content also decreases. “It can be seen from analytical results that the lower the temperature the better the concentration of Vitamin C in fruit juice.”³ Therefore I can conclude that my findings and my explanation is correct as it is confirmed by an outside source. Evaluation: Limitation of the method How significantly could this have impacted on your results and why Improvement When we diluted our lemon juice we didn’t use distilled water we used tap water. The distillation process removes many of the impurities present in regular tap water or drinking water. These impurities in the water could have interfered with the experiment. As tap water contains other chemicals, compounds and minerals which have the potential to also reduce or prevent the reduction of the DCPIP solution. This would have effected both the reliability and validity of my results. ...read more.

Conclusion

While conducting the experiment our lemon juice samples were left exposed to air. When oxygen in the air reacts with vitamin C, oxidation occurs which is a chemical change that results in the breakdown of this vitamin.â´ This would have caused some of our lemon juice samples to have a decreased vitamin c content due to the prolonged oxygen exposure, this would have caused more drops to be added to cause the solution to decolourise due to the combined breaking down of vitamin c from oxygen and temperature. We could cover the test tubes containing our 1ml samples and our beaker with the diluted lemon juice with clingfilm to reduce the exposure to air. While conducting the experiment our lemon juice samples were left exposed to natural and artificial light. Photodegradaton occurs when vitamin C is exposed to natural and artificial light. â´ This would have caused some of our lemon juice samples to have a decreased vitamin c content due to the prolonged light exposure, this would have caused more drops to be added to cause the solution to decolourise due to the combined breaking down of vitamin c from light and temperature. In a future experiment we could conduct it in a cupboard to completely reduce light exposure or we could conduct it in a totally artificially lit room to ensure that the exposure to light remained consistent throughout the experiment. Sources 1) http://uk.answers.yahoo.com/question/index?qid=20110221071452AA0OHqv 2) http://www.ask.com/question/how-does-temperature-breakdown-ascorbic-acid 3) http://www.pjbs.org/pjnonline/fin1877.pdf 4) http://www.enotes.com/homework-help/how-does-exposure-air-light-temperature-affect-310886 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. Marked by a teacher

    Neurology and Behaviour. Focus question: Is there an increase in the perception and ...

    5 star(s)

    investigation; however the main ones are that concerned with the potential human error and variables concerned with each participant which are likely to have had an effect on the rating of images and therefore the results in total. It is possible that by not controlling the individual differences between participants,

  2. Marked by a teacher

    The effect of Pectinase Concentraton on the production of apple juice

    occurring shows that as it reaches Pectinase concentration of 4%, the volume of apple juice produced does not increase as rapidly as seen between concentrations 1 to 3%. This may be because, as mentioned in the hypothesis, there are so many active sites in the Pectinase to react with the

  1. The effect of toliet cleaning products on E-coli ...

    Volume of cleaning product used Controlled variable (The volume of cleaning product used will be whatever is necessary to soak a paper disk. 1.2.2- Control experiment - A positive control which always inhibits e coli growth will be used (bleach), and a negative of control which never inhibits e coli growth will be used (water)

  2. Biology- Extended essay. For this research, I investigated the effects of DDT and ...

    It is found in the rivers of Myanmar that drain into the Bay of Bengal. It was introduced for the purpose of aquaculture, together with Catla (Catla catla) and Rohu (Labeo rohita) to other areas of India beyond its natural range in the early 1940's and in the 1950's and 1960's to other Asian countries5.

  1. How does cooking affect the amount of vitamin C in lemon juice?

    The resulting solution at the end of the titration, which comprises of DCPIP, lime juice and glacial acetic acid is a cloudy mixture. 1. Quantitative Data Lemon Juice sample Volume of DCPIP (± 0.1 cm3) Trial Reading of burette (± 0.05 cm3)

  2. Effect of Incandescent, Fluorescent and LED lights at 900 lumens on the concentration of ...

    For my investigation, I will be using the titration method to measure the abundance of ascorbic acid in different lights incandescent, led and fluorescent light at 900 lumens to find out the best light to store orange juice in that does not significantly affect the abundance of ascorbic acid present in oranges.

  1. Finding the vitamin C content of a lemon

    We continued with the addition until the indicator turned transparent. It first turned reddish and after that transparent which we needed. We found out that 2.73 ml of lemon juice is needed in order to turn the indicator transparent. We can conclude that this amount of lemon juice contains the same amount of vitamin C as our previous solution.

  2. What is the effect of pH levels on the net production, given by the ...

    uncertainty of +/- 0.1 in pH fluctuations from pH 7. 130 +/- 5 mL per trial used. 650 mL +/- 10 mL pH 8 buffer solution (Potassium Phosphate-Sodium Hydroxide) uncertainty of +/- 0.1 in pH fluctuations from pH 8. 130 +/- 5 mL per trial used.

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