You're asking the same question and apparently not doing much work of your own. Yes, it is a simple lab. No, it isn't a simpler answer. I searched Google, which you could do too, and finally came up with this equation. Red cabbage has a flavenoid in it. The particular flavenoid red cabbage has is an anthrocyanin. When an acid or base is added to this particular anthrocyanin, it changes color due to a conjugated system and the color ranges from purple to yellow to green. Here is the chemical equation for the various colors. I tried to copy and paste the equations but couldn't do it. You can do to this site and see the equations. You can also see that it isn't a simple explanation. Scroll down about 3/4 of the page to see the equations. After that I've listed another site that shows the various colors. You probably used something like that in your lab.
http://lecturedemos.chem.umass.edu/chemReactions4_9A.html
For the color chart scroll the next site about 3/4 down the page.
You can see it isn't such a simple answer. You can take these complicated equations and simplify them by saying that the chemical in red cabbage leaves adds or removes H when mixed with acids or bases which changes the chemical structure to produce different colors shown on the color chart.
http://www.coolscience.org/CoolScience/Teachers/Activities/CabbageJuice.htm
In the red cabbage lab, we just took the cabbage juice and in 5 separate cups mixed it with 5 different liquids, ex: coke, milk, cleaning agent, etc, and matched the color to a ph chart to tell if it was a base or an acid. Simple lab. The question needs a relatively simple explanation of what chemical changes occurred to turn the juice to a different color. I know it has something to do with the hydrogen ions and maybe the dissociation of the electrons, but I am not really sure how or why.
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Thanks for your help. I did google for 3 hours before I came here. You asked me to specify the lab I was doing so I did. Thank you again.
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