Science Buddies: "Ask an Expert"

I have a question for my science fair project (about Vitamin C levels over time and effects of temperature on Vitamin C). My Question is (for the background research) what exactly happens when Vitamin C is in contact with oxygen and goes through a process called oxidation (does it lose electrons, or something else?) and how do these changes (from being oxidized) affect the properties of Vitamin C.

Thanks for your help!

Hello Herospart,
I apologize to you that no one got back to you with an answer. Although my forum is typically biological sciences, I will do my best to help you. Thank you for your question.

So you are studying the effect of time and temperature on the effectiveness of Vitamin C, is that correct? It sounds like you are in the research part of your project. Here is some background information on a project that sounds similar to yours and helps explain redox (reduction-oxidation) equations. : https://www.sciencebuddies.org/science- ... background. Redox is the term used when talking about the exchange of ions within a solution; when electrons leave an element, it means that the chemical is being oxidized. When an element gains electrons, it is reduced. One way to remember this is to use the acronym, OIL RIG: Oxidation is losing (electrons); Reduction is gaining (electrons). Another acronym is LEO says GER: Losing electrons is Oxidation; Gaining electrons is Reduction.

This article can help you figure out the answer to your question, http://chemistry.about.com/od/demonstra ... ration.htm. Also to help you with some of the terms, reduction, reducing agent, etc, check this out: http://www.sparknotes.com/testprep/book ... ion7.rhtml.
When a chemical element loses it's electrons it is said to have undergone oxidation. But what happens to the electrons, do they just disappear? If one element donates or 'loses' electrons (oxidized), that means another must gain electrons (reduced). There is always an exchange. That is why it is helpful to draw out the formula. You should be able to draw out the change from Vitamin C being oxidized, meaning that it is losing electrons. Look at the Figure of the chemical structures (on the right side) of ascorbic acid and dehydroascorbic acid. Think about why it is called "dehydro": de- means taken out, hydro- means water. So how would vitamin c and dehydroascorbic acid be different? Does it undergo oxidation or reduction? Why? These are things you will want to explore and put into your research project. http://en.wikipedia.org/wiki/Vitamin_C.

Start with those resources and let us know how we can further help you. I look forward to hearing from you.