Geosmin is responsible for which smell?

Geosmin is responsible for which smell?

• A. Ammonia
• B. Chlorine
• C. Geosmin
• D. Ozone

Answer: (C)

That earthy, soil-like smell after rain comes from geosmin, a volatile compound produced by soil-dwelling bacteria such as Streptomyces and some cyanobacteria. It’s extraordinarily potent, so even tiny amounts released when rain wets the soil are enough to trigger that recognizable earthy aroma. The other substances have different, recognizable odors (ammonia is sharp and pungent, chlorine smells like bleach, and ozone has a crisp, metallic note), but they don’t produce the characteristic earthy scent. So geosmin is the source of that smell.

That earthy, soil-like smell after rain comes from geosmin, a volatile compound produced by soil-dwelling bacteria such as Streptomyces and some cyanobacteria. It’s extraordinarily potent, so even tiny amounts released when rain wets the soil are enough to trigger that recognizable earthy aroma. The other substances have different, recognizable odors (ammonia is sharp and pungent, chlorine smells like bleach, and ozone has a crisp, metallic note), but they don’t produce the characteristic earthy scent. So geosmin is the source of that smell.