Fruit Juice Mystery

In this chemistry challenge, learners work to figure out which of four juices are real, and which is just food coloring and sugar. Learners add vinegar (an acid) and washing soda solution (a base) to grape juice, cranberry juice, blueberry juice, and a fake juice mixture. The real juices will change color as an acid or base is added, while the fake will not. Background information briefly discusses how the colored chemicals in fruits are often themselves weak acids and bases, and how many plants have been used as sources of acid/base indicators. This activity requires adult supervision.