Walking Water Colour Wheel

We haven't done a science experiment for a while. Monkey's been really excited about all the art we've been doing so I've been running with that just in case he loses interest.

So I figured we were due for some science. This actually falls under the category of art, too - colour mixing. 

Supplies: paper towel, food colouring, water, glasses or clear plastic cups

Start by setting up the six glasses in a circle. They need to be close together. Fill every other cup about halfway with water. Then add five drops of the three primary colours to the glasses with water in them, ending up with one yellow, one blue, and one red. 

Next you need to prepare the paper towels. We use the rolls that have smaller pieces, so I took six pieces and folded them in half the long way. You could also cut them. They just need to fit inside the glasses. 

Once you have six strips of paper towel, you put one in each glass and then fold it down to arch over into the glass beside it. You should see two paper towels arching to the neighbouring glasses in each one, as in the picture below. 

Now you have to wait. This experiment does take some time. We saw the best finished results after a full twenty four hours, although you can see changes after less than an hour. 

After letting the paper towels absorb the water and "walk" it into the empty glasses, here's what we saw:

The coloured water moves through the paper towel and then mixes in the empty glasses. The three primary colours combine with each other to make the three secondary colours: green, orange, and purple. 

Blue + Yellow = Green

This was the most vibrant and obvious of our mixes. 

Yellow + Red = Orange

The picture doesn't quite show the true colour we could see, but this was the weakest mix we made. 

Red + Blue = Purple

To simplify the experiment a little, you could do each combination separately instead of in a wheel. It would use a few more glasses but it might be easier to  talk about. 

I've done this at school in the past and have had to elevate the primary colour glasses, I guess the height allows the water to move into the neighbouring glasses a little easier. I'm sure it can't hurt so if you feel it's not working that could be something to try. 

I'm sure Monkey is not a colour mixing expert after doing this activity but it is exciting to see the water moving, a little magical for him I think, and it's a fun way to introduce primary and secondary colours. 

Mar