Corn flour slime

So last week we filmed how to make homemade cornflour slime. Awesome stuff and so easy to make! We finished filming and the kids played with that mess for about a hour and half. There was so much purple everywhere, in Hunter and Rainer's hair, right down to his nappy! The beauty about the slime is that it's so easily washed off with water. so a nice bath afterwards got the kids in pristine condition. Click on the link below to check it out.....

cornflour slime

So here is the recipe for the slime in case it's hard to watch online as the footage sucks with me juggling how to do the experiment and children to boot ( mums and dads know this pain! )

Cornflour slime recipe

You need:

Cornflour ( about 2 boxes, depending on how much you want to make)
Water
Food colouring (any colour is good)
Mixing bowl ( and old tupperware or ice-cream container works)
Plastic spoon
Biscuit tray

Method

Place cornflour into the mixing bowl and add a little bit of water. (This is a great time to bring the kids in to get their mess on ) mix till it feels like a paste.

You will start to feel the mixture become slime-esque. it is now ready for a few drops of selected food colouring of your choice.

Now let the fun begin!
You can punch it, slide it through your fingers  or get stuck in it like quicksand!

Please note: DO NOT DISPOSE SLIME IN THE SINK!!! This will clog it up bigtime and you will have to explain to the plumber why a monster puked in your sink. no-no. Rinse the slime away after play out on the lawn with the hose or scrape it out and place into the bin accordingly. 

Dropping the science:

Cornflour has tiny starch particles that really like water. The water acts like a lubricant, when you drag your fingers slowly through the slime, the water can move easily between the starch particles. However, applying rapid force or pressure onto the slime (like a punch), it causes the starch particles that are almost touching each other to jam together and the water that was flowing between the starch to move out of the gaps causing it to thicken. This creates the slime to solidify. And hurt your hand if you punch too hard!

Cornflour slime laughs at the face of fluid dynamics.Fluids are gases and liquids. We have fluid that come in two categories. low or high viscosity. Low viscosity is the easy flow of liquid like water. High viscosity is the hard flow of liquid like cold honey. Cornflour slime is a good example of "shear-thickening fluid" where it can be low or high viscosity. Other examples of real world shear thickening fluid is toothpaste, blood,paint, pen ink and nail polish.