Thursday, December 12, 2019

Vitamin C free essay sample

Does the amount of Vitamin C on the label of commercially available tablet exaggerate the amount of Vitamin C? The aim of this experiment is to determine whether manufacturers of commercially available Vitamin c tablets exaggerate the amount of vitamin C Abstract: The purpose of this experiment was to test Vitamin C in commercially available Vitamin C tablets. It was discovered that the percentage Vitamin C content was lower than what was stated on the label. This, however, could be due to fillers and ionization, amongst other variables. Planning: Hypothesis: The amount of Vitamin C in the tablet is not exaggerated Independent variable: Dependent variable: Fixed variables: Indicator used: Phenolphthalein Apparatus: i‚ · Burette i‚ · Pipette i‚ · Beaker i‚ · Ehlernmeyer flasks i‚ · Glass rod (stirring rod) i‚ · Vitamin C tablet i‚ · Standard solution: 0,1mol. dm3 NaOH i‚ · Warm water i‚ · Indicator: phenolphthalein Method: 1. Crush one Vitamin C tablet, put it on a page and weigh it (take the mass of the page into consideration. Record the mass 2. Pour 75ml warm water into beaker 3. Mix the crushed tablet with the water using a glass rod 4. Fill the burette with standard solution (NaOH) up to the zero mark (make sure the tap is closed) 5. Run some NaOH solution out of the burette to allow the solution to flow through the tap as well. Record the amount of solution you have left in the burette 6. Attach the burette to a stand 7. Pipette 25ml Vitamin C solution into an Ehrlenmeyer flask 8. Add 4-5 drops of phenolphthalein 9. Put the flask underneath the burette with ample space for stirring 10. Open tap to pour standard solution into the flask. 1. Stir continuously 12. When the colour change starts to become more obvious and permanent, slow down, adding one drop at a time eventually 13. Record the amount of NaOH solution in the burette 14. Repeat steps 7-13 a minimum of 2 more times Results Vitamin C content on label: 600mg Mass of crushed Vitamin C tablet: 1100mg Water and Vitamin C solution: 75ml (25ml per trial) Drops of phenolphthalein: 5 NaOH concentration: 0, 1mol. dm3 Table showing the readings of NaOH (base) solution in the burette 123 Initial Reading (mol. dm3)015,531 Final Reading (mol. dm3)15,53146,5 Volume of base used (mol. dm3)15,515,515,5 Average volume of base used: 15,5mol. dm3 Balanced equation: H2C6H6O6 + NaOH i? NaHC6H6O6 + H2O NaOH c= n/v 0,1= n/15,5 n= 1,55 mols NaOH NaOH:H2C6H6O6 1:1 1,55:1,55 Volume of acid= 25ml c= n/vM= 2(1)+6(12)+6(1)+6(16) = 1,55/25 = 176 amu Ascorbic acid = 0,062mol. dm3 n= m/M gX1000= mg 1,55= m/176272,2g X 1000= 272200mg m= 272,2g The label says the Vitamin C content is 600g Therefore the actual % Vitamin C content= 272,2/600 X 100 = 45,3% Vitamin C Conclusion: In accordance with my results, the Vitamin C content in these tablets is exaggerated. However, there are factors that could alter these results, making them inaccurate. I therefore conclude that no conclusion has been made, until further experiments prove otherwise. Discussion: Vitamin C tablets are used to supply the body with the necessary amount Vitamin C that it didnaâ‚ ¬Ã¢â€ž ¢t get through diet. Vitamin C repairs and replenishes many organs, it is necessary for functions such as the biosynthesis of collagen and many more, and it prevents many diseases (such as scurvy). Too much Vitamin C can also be unhealthy and lead to problems, although most of the waste nutrients are excreted. It is, by law, that the Vitamin C content is stated on the packaging but whether or not the amount is correct, is unknown. Titration help us to calculate the actual amount of Vitamin C in a tablet but this could be inaccurate. Vitamin C ionizes easily, even more so in warm water. Therefore the amount of Vitamin C in the tablet could be higher because of this reason. Another reason for this amount is that these tablets contain fillers such as starch (which takes up space but doesnaâ‚ ¬Ã¢â€ž ¢t have any effect). Manufactures canaâ‚ ¬Ã¢â€ž ¢t put the incorrect amount of a substance on medicine because the repercussions could be hazardous. This experiment could also be inaccurate due to the number of titrations done. In the future more titrations should be done, the experiment should be done more precisely and efficiently, Bibliography i‚ · Ms Horn, The Settlers High school i‚ · Rudolph, Samantha,The Settlers High School Wesites: 23 January 2011 1. http://www. juliantrubin. com/fairprojects 2. http://www. sciencebuddies. org/science-fair-projects/project_ideas. shtml 3. afieldblog. om/2010/09/23/liesegang-rings-in-nature 4. classroom. all-science-fair-projects. com 5. http://www. projects. juliantrubin. com/science_fair_project/renewableenergy/solar_tracker_2. html 6. http://www. odec. ca/projects/2008/full8e2/ 7. http://www. free-science-fair-projects. com/Science-Fair-Projects-Search. aspx? Grade=11Category=All 8. n. wikipedia. org/wiki/Henrys_law 9. http://www. usc. edu/C SSF/History/2005/Panels/S05. html 10. http://wiki. answers. com/Q/Would_adding_spf_30_sunscreen_to_spf_50_sunscreen_make_it_sp f_80_sunscreen 11. http://www. instructables. om/id/Homemade-Sunscreen/ 12. http://www. instructables. com/id/Homemade-Sunscreen/ 13. www. ehow. com 14. http://www. super-science-fair-projects. com/medicine-health/suntan-lotion-ph-testing-science-projects. html 15. http://www. patentstorm. us/patents/5691158. html 21 March 2011 1. http://www. wisegeek. com/how-do-i-choose-the-best-vitamin-c-tablets. htm 2. http://www2. ohlone. edu/people/jklent/labs/101B_labs/Vit%20C%20analysis. pdf 3. http://www. anyvitamins. com/vitamin-c-ascorbicacid-info. htm 4. www. chemistryexplained. com 5. http://ods. od. nih. gov/factsheets/VitaminC-QuickFacts

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