Monday, May 4, 2009

Dancing Raisins Experiment

We did a fun and easy science experiment that I thought I'd share.  It was posted on a loop and we decided to try it out.  I had planned to do it with my younger boys and put the ingredients for the experiment in their boxes.  This was the same day I was doing science labs with my oldest two and the boys loved having their own "lab" too. 

It was such a hit, that Rebecca joined in too. 

Here is what you need for this experiment.

*Mason jar (I used the large size)



*Baking soda


You will fill the jar about 2/3 full of water. 

Next add in several "glugs" of vinegar. 

Next add a few raisins.

Finally,  comes several spoonfuls of baking soda.  Add one at a time in case your experiments starts bubbling over.  We had that happen to us. 

Without stirring, wait and watch.  (My boys kept wanting to add in a couple more raisins.)  The raisins will start to dance!

What you will see is the raisins starting to rise to the top of the jar, then falling back down.  Ours had a slow start and then picked up as time went on.  The raisins continued to dance for quite awhile too!  My children loved watching this.  It made for great entertainment while we were eating lunch.  LOL

The explanation behind the experiment is that the vinegar is an acid and the baking soda a base.  When the two combine they form carbon dioxide.  This attachs to the skin of the raisins in the form of bubbles.  When enough bubbles are on the raisin, it will rise to the top of the jar.  There the bubbles pop, and the raisins sink again. 

This was a good reminder to me that I need to do this type of experiment more often.  I'm hoping I can plan at least one per week.  My children loved it!  I thought it was fun to watch too.

Give it a try - I bet you'll like it too!