Science with Joseph

I said in a previous post that I was going to try to do regular science experiments with our son Joseph, age 7.  He loves science and especially loves hands-on science.

The little book I've been using, Simple Science Experiments with Everyday Materials by Muriel Mandell, has been invaluable.  Most of the experiments really do have everyday materials that we have around the house.

Here was an incredibly simple experiment.  I boiled water and poured it into the bowl on the left.  I put water in the one of the right and added ice cubes until the water was quite cold...then I removed the ice cubes.  Joseph chose green food coloring to test diffusion properties as a function of water temperature.  You can see that the food coloring in the hot water bowl diffused far more rapidly than the food coloring in the cold water bowl. I talked a bit about how hot water molecules are moving faster and bouncing around more, so that the food coloring spreads quickly.

  This experiment was a bit more complicated.  Joseph collected 15 pennies and we added vinegar and a pinch of salt.  After a few minutes, the vinegar and salt had removed the outer corrosion products and left a bunch of shiny pennies.

  Then we got a plain ordinary nail.  I scrubbed it with a wire brush to remove any dirt on the outside, and dropped it into the solution of vinegar and salt.

  15 minutes later...

  Voila!  Copper was deposited on the nail!  The nail on the bottom is the one that sat in the vinegar/salt solution. The one on the top is an untreated nail for comparison purposes.

  Why did this happen?  The acid in the vinegar dissolved some of copper into solution.  The iron in the nail is less chemically active than copper, so the copper deposited onto the nail.

    I didn't think it would work so was very pleased when it did!