100 Days Project

Nanogirl: Star Science

Nanogirl wants to find 100 friends to do science experiments with her to prove that no matter who you are or what your education level, you can always have fun with science.

Day 29:

14 year old Nick discovers hydrophobicity

A surface that is hydrophobic repels water and today Nick and I learned that even the common broccoli has this unique feature.

We dropped water onto the leaf of a broccoli and watched it ball up and roll off rather than it getting wet.

Broccoli leaves can do this because they are covered in a tiny layer of wax particles which are so small you need a very high powered electron microscope to see them.  These particles make the leaf surface very rough at the nano and microscale and combining the roughness and the wax reduce the contact area between the water and the leaf surface causing the water to run off.

There are other vegetable leaves which show the same effect too, can you find out which ones they are?