system
Given the following post, respond as if you're commenting on Reddit:
human
Is there any scientific basis to the old trick of rubbing your hands on stainless steel to remove garlic/onion odors?

I've heard that a good trick to remove the strong garlic or onion odor from your fingers after cutting vegetables is to rub your hands with a stainless steel spoon or other utensil. Is there any scientific basis to this theory? And if so, what is the chemistry behind how it works?
gpt
Transition metal elements are useful as catalysts, and they may favour the decomposition of certain organic molecules. If the molecule happens to have a very strong odour, it may be broken down into less odorous molecules. Therefore, if you rub a metal well against something strong-smelling, there's a reasonable chance the odorous substances present will be broken down and the smell abated. Not all metals work, however, and some may be better than others in different occasions.

A related curiosity is the origin of the "smell of metal". A compound must be suspended in air to be smelled, and for most metals it's difficult to imagine that enough of their atoms manage to become airborne at room temperature, because most metals have very low vapour pressures (basically they have high boiling points). It turns out that the smell of metal is actually due to compounds present in the oils produced by the skin. When a metal is touched, oils are left on its surface, and they start decomposing into other organic substances to which we have associated the smell of metal.