Dancing Raisins

I recently bought this Primary Science Set from Quality Classrooms, which is a great beginner's science kit. It comes with 2 mini test tubes, 1 large test tube, tweezers, a beaker, a flask, magnifying glass, dropper and goggles. It also comes with 10 easy science experiments. Sammie loves wearing the goggles around and doing "periments" :)

Over the next few weeks, we will be doing and sharing our results from the experiment cards that came with the set. Including purple volcanoes :)

We decided to try out the Dancing Raisins experiment. The experiment is to drop raisins into clear soda and watch what happens. Only I changed it up a little bit from what was written on the card.

The weather was so beautiful that we set up our science lab outside on the patio :)

I gathered up some dried fruit, (2 kinds of raisins, currents, blueberries, and cranberries), some frozen fruit and vegetables (blueberries, peas, carrots, green beans and corn).

Maddie filled the beaker up to the 1 cup mark with 7-Up and Sammie started dropping some different kinds of raisins into the 7-Up.

The first thing she dropped in was a yellow raisin, it just sank to the bottom and sat there :( Not very exciting.

Next she put in a brown raisin, it sank and then floated up to the top :) That was pretty cool to watch. It would float and then sink, then float back up again.

Maddie wrote all their observations down in a little notebook :)



They tried out all the dried fruit, and all of them, except the yellow raisin, danced in the 7-Up

Next they put in the frozen veggies and fruit. They all just floated and didn't dance

The girls decided to take the experiment a bit farther and see what would happen if they dropped the same items into plain water.

All of the items sank, except for 1 pea that floated. None of the items danced

Sammie checking out a floating carrot :)

They then mixed the water and 7-Up together in equal parts, to see what would happen.
Everything, except one pea and one carrot sank.

After we had experimented with the frozen and dried items, we went and gathered up some more items, grapes, rice, macaroni, and dried beans. They kept experimenting :)

All of the new items sank in the 7-Up, except the grapes, which danced :) They also all sank in plain water, and a mixture of water & 7-Up.

The grapes really danced in the 7-Up. It was much easier to watch them dance, than it was the raisins, as they are so much bigger. :)

Sammie and Maddie had a great time with this experiment :) We didn't really discuss at all, the reason why some of the items danced. I just let them play :)

But if you are interested in why the raisins and grapes danced in the 7-Up. Here is what I understand.

The "fizz" in the soda is carbon dioxide, which builds up bubbles on the raisin. Enough of them build up and causes the raisin to float to the top. At the top, the bubbles are popped, causing the raisin to drop. Then it repeats over and over :) This also explains why nothing danced in the plain water or the mixture, as there is no "fizz" in water and probably not enough in the mixture.

I'm not sure why it only worked with the dried fruit and grapes and not with the other items.

If you have any ideas as to why only the grapes and dried fruit "danced" or if you liked this post, we would love to hear from you, either through a comment here or join us on our Facebook page