Coffee, tea, or cocoa. A trio of experiments including the isolation of theobromine from cocoa.
D002099:Cacao; D002621:Chemistry / Q000193:education; D003069:Coffee; D008722:Methods; D013662:Tea; D013805:Theobromine / Q000302:isolation & purification*
D003069:Coffee; D013662:Tea; D013805:Theobromine