This experiment is appropriate for grade school aged children. Simple items such as oranges, indophenol, a vial, an eyedropper, a metric thermometer, a pan and a 25 mL graduated cylinder are used in this experiment. Indophenol is an indigo colored metachromatic dye and is used to determine the presence of ascorbic acid or vitamin C. This experiment is safe for grades 3 through 6 under proper adult supervision.
Testing for the effects of light on vitamin C content in juice is an experiment suitable for middle school aged students. There are many factors which can affect the amount of vitamin C found in juice. Frozen juice concentrate typically has higher vitamin C content than fresh juice, but the amount of vitamin C content is also dependent on which type of orange or fruit was used to make the juice.
This project is best completed by high school students in grades 10 through 12. Students will learn how to measure the amount of vitamin C using the iodine titration method. Results are compared between homemade orange juice, high-quality not from concentrate orange juice and juice made from frozen concentrate. To complete this experiment, students must have a clear understanding of the terms titration, stoichiometry, vitamin C and iodine.
Citrus fruits can be used to generate an electrical current. For this experiment, lemons or limes are often used. The experiment demonstrates that an electrical current strong enough to power a light bulb is created. The experiment takes between five and 10 minutes and can be completed using lemons, limes, grapefruit or oranges. Common items such as electrical tape, copper nails, galvanized nails, and small light bulbs are used. A micro ammeter is also used during this experiment, which is a measuring instrument often used for measuring electric current in a circuit.