Interdependence. Interdependence is a key idea in science. As students learn about science, they begin to understand that the earth is not a group of discrete parts but a continuous environment existing over time as well as place.
In order to remove the caffeine from coffee beans, the beans are washed in a solvent (a liquid capable of dissolving substances), transferring the caffeine from bean to liquid in a process known as extraction. To extract caffeine from whole coffee beans, the following solvents can be used:
The first successful extraction of caffeine from coffee beans was achieved by a German chemist, Runge, in 1820. He was not trying to make decaffinated coffee however. He was looking for compounds that might explain his insomnia.