I found this experiment ages ago on this website and forgot all about it! Then the other day I stumbled across the same experiment on Life with Moore Babies blog, and decided to go out and buy a big bag of skittles before I forgot again! So today was the day...
This is what we started with:
1. Big bag of skittles (you won't need many, but they're tasty...)
2. Bowl of HOT water (you can wait to microwave it just before you add the skittles, or use boiling water)
3. Five pipettes (alternatively you can use a syringe or spoon)
4. A tablespoon or measuring spoon
5. A glass
6. Five bowls, or glasses - microwave safe
Step 1
Let the littlies sort skittles by colour.
Step 2
Decide how many skittles you want to use of each colour. All the guides I looked at said purple - purple - 10,green - 8,yellow - 6,orange - 4, red - 2.
After looking at some other pictures I wasn't convinced two skittles difference between each colour would be enough to make the rainbow stand out. We chose increments of three.
Purple - 15,green - 12,yellow - 9,orange - 6, red - 3.
Step 3
Put two tablespoons of HOT water in each glass. If you boil the water then glasses are fine, if you heat the water in the microwave make sure the water is in bowls or something else that easily fits into the microwave. We gave each glass 1 minute in the microwave.
Step 4
Put the skittles into the glasses of water, one colour in each glass. They dissolve better if you stir them, and also when the water is really hot. If it starts to cool down put them back in the microwave. We put them in a couple more times for 30 seconds to keep the water hot. They dissolved quite quickly, however if you leave them to dissolve on their own they can take hours apparently.
We then left the glasses to cool to room temperature because the cooler water is, the denser it becomes... So kinda defeats the object of the density experiment if they're all slightly different temperatures anyway.
Step 5
Pour the purple into the empty glass. From now on be very careful. Don't move the glass you are putting the colours into. Don't knock the table - the colours will mix.
Use a pipette to suck up the yellow colour. Hold the pipette tip against the glass near the top. Squeeze it slowly, whilst running the pipette (slowly) around the inside of the glass.
This helps to layer the colours, if you go to quickly or pour the water straight in they will mix.
If you don't have a pipette do the same with a syringe, or alternative you can apparently pour it against the back of a spoon so it runs in more smoothly - but I've read that the spoon method doesn't work so well.
Use a different pipette for each colour as they mix easily and ruin the pretty rainbow colours.
As you can see our experiment was successful! It's actually much clearer in real life, and I struggled to take a picture where you can see the red/orange divide clearly.
So what did we learn?
Each glass started with the same amount of water.
Each coloured solution we made had a different amount of sugar (skittles = sugar).
The more sugar (skittles) added to the original amount of water, the more dense that solution became.
I kinda wish we'd learnt more to be honest... but density is slightly beyond my 4 year old at the moment... so I can wait a bit longer before I have to truly understand what makes some substances more dense than others ;)
What else did we learn?
That when you suck skittles they turn white. They have hard sugar shells, with food colouring. Saliva disolves the colouring (Jakob learnt two new words... I wonder which ones they were :p).
When you mix the rainbow, the sugar water all mixes together (with the colouring) to make one solid glass of brown sugar water.
Linking this post to the Sunday showcase and Science Sunday and Learn through play blog hop
