Some molecules respond to light in a matter of seconds. In the case of this dithienylethene compound, ultraviolet light triggers a ring-forming reaction, turning the colorless solution deep red.

Believe it or not, this is an unaltered photograph of the interface between two solvents used in a routine extraction procedure. Viewed close-up under ultraviolet light, the layers look like a ...

As it turns out, instant films are all about chemistry! So, how are these pictures made? The special film used for Polaroids looks thin and shiny, but it’s actually quite complicated. Each film ...