Learn a little bit about adhesion, cohesion, and capillary action! Share your experiments in the comments below.
1. Coffee filters
4. Water based markers
Step 1: Take your coffee filter, unfolded and draw whatever you’d like inside of the center circle. (just make sure it’s almost completely covered in marker ink)
Step 2: Fold your coffee filter in half, then in half again.
Step 3: Add just a bit of water to your jar, it should be less than half way full. If you’d like to experiment with different water amounts, you can do that too. Folding your coffee filter again to make a “cone” sort of shape, drop your coffee filter into your jar.
Step 4: You’ll immediately see the water begin to rise to the top of the coffee filter. You can take it out after a few minutes and most likely it will be completely wet by now.
When dry, your coffee filter will also have a cool pattern like this!
Why did the water travel upwards? What does this have to do with adhesion and cohesion?
When there is less cohesion than adhesion, capillary action takes place. This causes the water molecules to travel upwards (or across) the surface.
In our experiment, water moves along the tiny “gaps” in the fiber of our coffee filter.
Adhesion – the action of adhering/sticking to a surface
Cohesion – the action of forming a whole (unity/connection)