Book 9, Question 42
Why Do Some Smells Seem ‘Loud’ Even in Tiny Amounts?
Some smells seem loud even in tiny amounts because human noses can detect some molecules at super-low doses! Smells like toasted bread or vanilla are easy to notice. Our noses are very good at spotting useful smells.
More fun facts
- A chemical called skatole is a big reason poop smells bad.
- In tiny amounts, though, skatole has a flowery smell and is found in orange blossoms and jasmine.
- Perfume makers even use skatole, in very small amounts.
- Natural gas has no smell, so gas companies add smelly chemicals called mercaptans to make leaks easy to notice.
- Humans are remarkably good at smelling. In one experiment, people compared mixes made from 128 different smell molecules.
Sources: Scientific American, BBC
Questions kids ask
Why does gas for stoves smell if it has no smell?
Gas companies add smelly chemicals called mercaptans so a leak is easy to notice.