Why do we have a nose, rather than just two holes? © Getty Images

Can smells travel through liquids?

Who 'nose' what you might be able to smell underwater.

Asked by: Stan Arlington, by email


They certainly can, just as they can travel through solids like plastic packaging.

The two main differences between the movement of aroma molecules in air and their movement in liquids or solids are the concentration of the molecules and the speed at which they can travel through the medium. In water, the concentration can be extremely low because many aroma molecules have only minimal solubility in water.

The speed of diffusion of the aroma molecules is also much slower than in air because there are many more solvent or solid molecules in the way.

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