Vitamin C (ascorbic acid) is a water-soluble nutrient which is found in certain foods. It acts as an antioxidant (inhibits oxidation) in the body, helping to protect cells from the damage caused by free radicals. The body requires vitamin C in order to make collagen, a protein essential to help wounds heal. Vitamin C also improves the absorption of iron from plant-based foods and helps the immune system work properly to protect the body from disease. [1] The purpose of this practical investigation was to find out which juice, orange, pineapple or grapefruit, contains the most vitamin C, and to calculate the percentage of vitamin C in each fruit juice. The hypothesis deduced was that Orange juice will contain the most vitamin C, in order to determine whether this hypothesis was correct or not, it needed to be tested practically; to do this you need the different fruit juices – they are the independent variable, DCPIP (dichlorophenolindolphenol) 1% is a blue dye which decolourises as it becomes reduced – this is the dependent variable (measure how much fruit juice is required to turn 1cm3 of it colourless/slightly pink), and 1% vitamin C solution to have as the control variable, it should be treated like the fruit juices.
You must to take into account any hazards (situations that pose a level of threat to life, health, property, or environment) [2] that you may encounter when conducting any practical investigation: Hazard | Outcome of hazard if it is realised | How to control/reduce hazard | DCPIP solution getting into eyes | Less risk of damaging eyes | Wear goggles, handle solution with care | Spillage of water/solutions | Less of a chance of falling over due to spillages | Place water/solutions away from edge of desk, and clear desks of unnecessary things to avoid knocking them over | Glass (beaker) smashing | Less risk of getting cut by broken glass | Don’t pick up glass with wet hands, place glass