Density of Water Experiment {Science Sunday}

Not all science experiments go according to plan, which means although it was a bust, we still had the opportunity to talk about what should have happened and how the experiment went wrong. Or better yet, if at first you don’t succeed, Mommy will try, try again until it works the way it was supposed to {‘cause she’s a little crazy like that}.

Question of the Week…what would happen when a bottle of warm water {red} was place upside down over a bottle of cold water {blue}?

Items we used for this experiment:

~ two glass jars

~ hot and cold water

~ blue and red food coloring

~ piece of cardboard

Predictions and Experiment…

Each of the kids made a prediction about what would happen to the waters when the piece of cardboard was removed from between the two jars…would the colors mix, stay the same?

We put the cardboard on top of the warm water, inverted it and then pulled it out from between the jars.

This is what happened {and what wasn’t supposed to happen}. The colors mixed.

Obviously the water spilled too, but there was just too much of a ‘drop’ when the cardboard was removed and it just plopped into the container below.

The Nutshell Reason…

The warm water is {supposed to be} less dense than the cold water and liquids of different density will {usually} not mix. The warm water SHOULD have stayed above the cold water ~ floating above the cold water.

After the Experiment…

We recorded our results on our experiment sheets, telling what happened and also what should have happened. I couldn’t leave well enough alone and decided to take matters into my own hands and try to get the experiment right {I know…my brain drives me nuts like that!}.

In an attempt to get the experiment right, I filled each of the jars up to the very top. I also used a thinner piece of cardboard because the ‘drop’ of the water when the cardboard needed to be pulled out was too much.

The result?  SUCCESS!!!!

Resource for this experiment: How to Do Science Experiments with Children is available from Amazon and you can also check it out {and do some of the experiments} using Google Docs! The experiments use easy-to-find objects and also include record sheets for kids to fill out with their predictions and experiment results. Each experiment also includes teaching tips and explanations…which are rather handy! :) Don't forget to check out some other great science ideas at Science Sunday hosted by Ticia at Adventures in Mommydom.