NextPrevious

The World Around Us

Chemicals in Our World

Why do farts stink?

Farts are mostly nitrogen (N2), but that’s an odorless gas. The smelly molecules in farts are mostly sulfur-containing compounds that reek like rotten eggs. Other odoriferous compounds include skatole and indole. How did chemists figure this out? They analyzed fart gas by gas chromatography. No, really.

Image