Monday, March 21, 2011

More Fun With Oil And Water Density - Rainbow Lava Lamps and Ocean Bottles

Our Science Sunday experiment (or Science Monday, if you want to get technical), started out as a quick Family Fun inspired, rainbow of "lava lamps", to kick spring off right.

It's been nearly a year since we've made an oil, and water "lava lamp", and last time we use Alka Seltzers to keep our bubbles moving.

This time, we started with six glass jars, filled 3/4 full of water.


Then, we added food coloring to make our rainbow (just two drops in each jar)...



...topped the jars off with 1/3 cup of cooking oil each...


...and dumped in some table salt.


Just as Family Fun promised, the salt weighted the oil down, causing it to sink under the water, then as the salt dissolved, the oil "bubbles" were released, and rose to the top.




It wasn't quite as much fun as the Alka Seltzer version, but it was interesting to see the oil straining against the salt, as it dissolved, trying to rise to the top.

And, we noticed the colored salt water against the layer of oil, had a neat, ocean like effect.



So, of course, we had to make an "ocean bottle", again with oil, water, food coloring, and salt...


...but also with toy sharks...


...and a Lego "scuba" diver.


After oohing, and aahing over the larger "lava lamp", the little ones, who only vaguely remember our previous oil and water experiments, took it to swoosh waves back and forth...


...discovering in the process:

  • no matter how much you shake the bottle, the oil and water will not mix,

  • oil always rises to the top of the water,

  • the food coloring will only dissolve in the water, and not the oil,

  • our toy sharks do not float,

  • our Lego man floats in water, but not in oil.


All in all, it was a very interesting, and satisfying experiment. Oh, and the children want you to know, that no shark, or Lego toys were harmed in the process.



Don't forget to check out this week's Science Sunday link-up, over at Adventures of Mommydom, for more science themed fun.

It's great to be a homeschooler.

9 comments:

Christy said...

That is a fun science experiment!

Phyllis said...

That sounds like so much fun!

Kylie said...

oh lava lamps, I still haven't done these with my kiddo's!

Debbie said...

Looks like a lot of fun. It must have been a very rainbow day, as I can see hoping around the different blogs.

Ticia said...

It's good to hear they survived, and no one was seriously hurt.

An Almost Unschooling Mom said...

Ticia - I'm not sure I can say as much for the Lego guy frozen in carbonite, in the freezer :)

Carmen said...

ooooo! We want to do lava lamps!

Raising a Happy Child said...

Love it - we will definitely try it too, especially the ocean in the bottle.

Andrew and Sharon said...

We just tried this and it worked awesome! We're going to start homeschooling when my son starts Kindergarten this fall- well, we really are already, and loving it so much! Thanks for your blog! I'll be following you :)