
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.
Read more:
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.
Authors

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
Sponsored Deals
Subscription offer
Subscribe and try your first 3 issues for just £5. After your introductory period you will pay just £22.99 every 6 issues by Direct Debit. Receive every issue delivered direct to your door with FREE UK delivery.