Chemistry

If you ask Arielle, she would say she hates science. When she was younger we did a couple of years of zoology and then later botany, astronomy, and an introduction to physics. Nothing much has interested her. This year we are doing a middle-school level chemistry. Still, no spark, except for one brief moment yesterday.

We were learning about acids, bases, and pH. We made an acid/base indicator with red cabbage. Do you know how to do this? Very easy! Put 3 cups of distilled water in a pan and add a whole red cabbage, chopped in several pieces. Bring to a boil and continue boiling about 15 or 20 minutes. Strain out the cabbage and save that dark purple juice.

After preparing our cabbage juice, Arielle cut a white coffee filter in strips and with an eye dropper, dripped the liquid over the strips. We made our control acid--vinegar mixed with a little water and our control base--pure ammonia mixed with a little water. Then we gathered several light or clear colored liquids: Sprite, tap water, milk, lemon juice, orange juice, a little squeezed juice from a ripe tomato, Windex, bleach (careful!), dishwasher soap.

Our coffee filter/litmus paper was not dry yet and we were anxious to begin, so we just put a little of our vinegar in a glass bowl and added the cabbage juice. The vinegar turned bright pink! Then came the even more exciting moment. Arielle dropped some cabbage juice into the ammonia. Instant green! She said, "Cool!" She tested our other liquids and had fun observing the results. (Caution! Never mix bleach and ammonia. I warned Arielle that this is a chemical reaction we don't want to see.)

Well, it wasn't enough interest to spur her onto a career in chemistry, but it was something! She now has all these cool strips of paper too that she can dip into any liquid to see if it is an acid or base. I think we need more hands-on projects.