cart Shopping Cart cart(0)

Food colour swirl

You will need:

  • 1 white plate
  • 1 eye dropper, pipette or straw
  • Water
  • Food colourings
  • Rubbing alcohol/methylated spirits
  • Adult help


1. Fill the plate with water.

2. Add food colouring in the position of the blue dots

3. Add the methylated spirits/rubbing alcohol in the cross position

4. What happens?

Why Does This Happen?

All liquids have a property called surface tension.

Surface tension is like an invisible 'skin' that holds the liquid together. It turns out that the surface tension of water is much stronger than the surface tension of alcohol. The surface tension within the water is stronger, pulling the food colouring away from the alcohol and causing the swirling effect you see as the alcohol mixes through the water. 

Surface tension is caused by cohesive forces between the molecules that make up the substance. The molecules right at the edge of liquid are pulled more strongly into the liquid than into the surrounding air. You see this whenever water is 'beading' on a smooth surface, with the water minimising it's surface area to the surrounding air.

Join our newsletter for more science teaching thoughts & ideas

Join the Fizzics newsletter

Back to Kitchen Chemistry science experiments

>100 Free Science Experiments on this site!

Coloured shadows
  • Experiments to colour your class!
  • Easy & fun
read more
skeleton and student
  • Make fake blood & more!
  • Biology made simple
read more
electricity experiments
  • Circuit science for kids
  • Cheap materials found easily
read more
Vortex rings made with fog
  • Experiments using Newton's Laws
  • Step by step science
read more

School Science Visits: 

  • Highly engaging & curriculum-linked
  • Additional Teacher Support Resources
  • Professional visits in-class or via video conference
  • Both Primary School & High School science incursions
Call 1300 856 828 or use this form to discuss or make a show booking for your school!

Email updates

Signup to our monthly email Learn more

Contact us

1300 856 828

5 St James Place,
Seven Hills NSW Australia
facebookgoogle plustwitter
linkedin youtube   ico6 pinterest