Why can I smell solids as well as liquids and gases? © Getty Images

Why can I smell solids as well as liquids and gases?

Gases, liquids, and even some solids. We can smell them all as long as some of the object's molecules can enter a gaseous state.

Asked by: Tracy Stott, Selby

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We smell gases because their molecules are free to enter our noses. We smell liquids because some of their molecules enter the gas phase after escaping from the liquid surface. Solids can also release molecules to the gas phase, albeit slowly, but the usual reasons why we can smell them are that they contain volatile oils (such as most woods), or that they are chemically reacting with something from the atmosphere to produce a gas.


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