Lukas tested different juices for vitamin C as part of the lesson on nutrition for human anatomy and physiology class.
Here he's making his vitamin C indicator, stirring iodine into a cornstarch/water mixture.
Now he's adding the indicator into the different glasses, labeled with the juices he's testing: two kinds of bottled orange juice, fresh orange juice and fresh lime juice. We also added a test for milk to see if it has any vitamin C.
Now he's adding the juice to the vitamin C indicator.
And here are his results! Fresh orange juice had the most color change, so it has the most vitamin C. Even fresh lime juice didn't have quite as much vitamin C. Milk doesn't have much vitamin C in it.
Lukas was chagrined to learn that his hypothesis that Minute Maid orange juice would have the most vitamin C was wrong. But I told him it was ok to be wrong with a hypothesis: that's what happens when scientists do an experiment--they learn!