Summary; In this experiment, I learned that freshly squeezed orange juice will contain more vitamin C then juices from concentrate and that lemon contain more vitamin C then oranges. Ascorbic Acid Also known as: l-ascorbic acid, vitamin C, ascorbate A six carbon compound related to glucose. Objevtive: To analyse the concentration and percentage of different food sample by using titration method and state whether the percentage and concentration of vitamin C. Vitamin C or L-ascorbic acid is essential for normal growth of humans and it helps in the repair and reconstruction of body tissues lost over time. Ascorbic Acid: metabolism and function of a multifaceted molecule. To differentiate between fresh squeezed fruit juices and commercial carton fruit juices.
If we can control all the variables properly, this reduction rate should also be an indication of the rate of photosynthesis since the light and dark reactions are coupled. Vitamin c in fruit juice using dcpip titration Preparing the standard ascorbic acid solution 1. Make sure that if you are diluting a reagent that you calculate the effective concentration of that reagent in your protocol. They are found in all the foods that we eat, and must be consumed in small quantities since our bodies cannot make them. Sandals and open toed slippers are a strict no no and should be avoided.
Distances such as 16, 17 ,20 ,22, 25, 27 would have been extremely useful for two reasons. This graph shows the average values plotted and their respective error bar. Read all procedures thoroughly before entering the laboratory. Antioxidants are nutrients that block some of the damage caused by free radicals. Repeats can be carried out 2 times to obtain mean results.
Between readings, cuvettes 1, 4, and 5 should be placed in the back of the room under high light conditions. The rate of disappearance of blue color over time is directly proportional to the rate of oxygen evolution from the chloroplasts, and thus is a good measure of photosynthesis. Consider what to do if your results give very different measures than those quoted by manufacturers. In isolated chloroplasts, light is required as the name of the observed reaction states, light dependant reaction. This was highly likely due to the heat radiated by the lamp, causing the rate of reaction to be higher than as if it were only due to light intensity. The concentration of vitamin C is more in freshly blended fruit juice that can be useful for human.
Teaching notes Traditionally the production of oxygen and starch are used as evidence for photosynthesis. Save the green pellet chloroplast-enriched fraction. Health and safety checked, September 2008 Related experiment. If vitamin C, which is a good reducing agent, is present, the blue dye, which turns pink in acid conditions, is reduced to a colorless compound by ascorbic acid. Note the absence of sorbitol.
Proceedings of the Royal Society B: Biological Sciences. Vitamin C tablet 1 tablet per one trial 4. Because the body breaks down Vitamin C very quickly and does not store very much, we need to eat Vitamin C containing foods. Similar increases in the rate of reduction can also be stimulated by a dilution technique. Throughout the procedure, be sure to wash glassware with water and the round bottom centrifuge tubes that have come in contact with chlorophyll using 70% ethanol.
For inhibitors, the effect is concentration-dependent. The results also prove my hypothesis is right that lemons contain more Vitamin C. In this case a non-linear regression test would have been the most suited for testing the relationship. Choose the Orientation of the printout portrait or landscape. Those who experience any of the above negative symptoms should see qualified family practice doctors to talk about what may be the issue and whether a dietary deficiency may be the root cause. Current Opinion in Plant Biology 2000, 3:229-235. With strongly acidic juices such as lemon juice this could confuse determination of the endpoint.
Tube tubes were placed 37 mm, 27 mm, and 5 mm away, respectively. The grinding can be done in a mortar and pestle, or using a blender for larger samples. Fruit, Laboratory glassware, Measure 324 Words 2 Pages Acid Determination of Vitamin C Tablets and Salt Solutions Chem 1290-016 03-05-2010 ------------------------------------------------- Purpose: The purpose of this lab was to use acid-base titrations to find the mass percent of ascorbic acid in a Vitamin C tablet. The body is not able to make Vitamin C on its own so therefore it is important to include plenty of Vitamin C- containing foods in your diet. The best way to extract vitamin C, and for human to benefit from fruit juice is when fruit juice is freshly blended or squeezed. The experiment users an new and old lemon, orange and blackcurrant juice, each with varying amounts of vitamin C content. The experiment carried out was to measure the content of Vitamin C in the selected fruit samples, from the results I can conclude that the results were accurate, reliable and precise therefore allowing me to state this conclusion and to prove my hypothesis right! The endpoint is determined by the formation of blue-black starch-iodine complex when all vitamin C is oxidised and excess iodine is free to react with the starch solution added as indicator.