I recently soaked my sons onesie overnight in water and oxiclean. The legs and feet were sticking out of the bowl onto the counter. The next morning most of the water had traveled up and out though the legs (this bowl was not short either, it was part
Of our salad spinner.)
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ELI5: Water likes to touch hydrophilic materials. Materials that are hydrophilic and have a lot of small pores/channels/capillaries (paper or clothes) are really good at sucking up water. This is the same mechanism (and material) for how plants and trees get water up and into their leaves.
Overexplained: to see how much water likes a solid material, we can put a drop of water on it. If it flattens out a lot, the surface is hydrophilic. If it beads up like on a Teflon non-stick pan, the surface is hydrophobic.
The quantification of this is the contact angle. A shallow, spreading contact angle <90 degrees is hydrophilic, and a steep, beading contact angle >90 degrees is hydrophobic.
The contact angle is best described as a competition for the surface at the molecular level: which prefers the surface more, water or air? In science, this is the 3-phase contact angle (material, water, air). You can also imagine repeating this measurement, but swapping the material for a different material, swapping the water for a different liquid like alcohol, or swapping the air to a different gas like argon (or swap the gas for a liquid like oil).
Source: am microfluidics engineer
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