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Fundamental question about 'smell'

  1. Sep 9, 2008 #1
    As I understand it, the sensation of smell is caused by small amounts of matter leaving the body before being incident on olfactory receivers in our nose. Now, since the 'smell' has mass and it is leaving the body, could there eventually arise a situation where some body loses all its mass as 'smell' and ceases to exist?

    Intuitively this seems correct, and I can point to my anecdotal evidence of books smelling 'stronger' as they age and deteriorating in condition, but if this is not the case then can somebody explain to me how smell actually works?
  2. jcsd
  3. Sep 9, 2008 #2


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    Yes, a body can lose all its mass as smell (or equivalently, you can consider the body to have become completely spread out to whereever all its smell molecules went).

    Books getting smellier may have not much to do with losing mass. Things can get smellier through a chemical reaction - if you fry chicken, it becomes smellier (in a good way, usually), but that's mainly because the chemicals it is emitting are different, and your nose is more sensitive to the new chemicals from the chicken.
  4. Sep 10, 2008 #3


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    Perhaps a better example is one of those plug-in air fresheners that heats and volatilizes a solid. After a while, the smell goes away because the material has evaporated. But most of the solid objects around us (other than ice) have negligible vapor pressure and won't be vanishing any time soon.
  5. Sep 15, 2008 #4
    If water smelled like something you would smell it when you are around it. If you started boiling it, it would be a stronger smell. Look up vapor pressure.
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