why is 1 subtance hydrophillic and another hydrophobic. Can you change the behaviour of a substances ?

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why is 1 subtance hydrophillic and another hydrophobic. Can you change the behaviour of a substances ?

In: Chemistry

Water is a polar molecule, meaning it has positive and negative sides, kind of like a mini-magnet.

Hydrophilic surfaces are usually polar too, so they attract the water molecules like magnets clicking together. So water will easily “stick” to the hydrophilic surface and, if the substance is porous, be absorbed into it.

Hydrophobic substances are usually non-polar, so water doesn’t stick to them like how magnets on wood won’t stick. Since there is no attraction between the water molecule and the surface, it easily rolls off the material.

Soap is both.

One half is neutrally charged ie is hydrophobic, which another poster pointed out means it can interact with hydrocarbons. The other end is charged, and is thus hydrophilic and interacts with water.

Combined, soap allows hydrocarbons to be dissolved in water.