First get permission to use kitchen equipment and ingredients.
1. Pour the grape juice into the glass.
2. Slowly mix the baking soda into the grape juice. The color at the top of the juice will change to blue.
3. Now add the vinegar to the mixture, a drop at a time. The color will change to pink where the vinegar drips.
4. When you pour out the liquid in the sink, notice how dark it has become.
Grape juice looks purple because its molecules are arranged in such a way that it absorbs all the colors of light except purple. The purple reflects back to your eyes. This is how you see color. Adding other substances changes the molecular structure of grape juice, so its color changes.
