A simple balls-and-sticks model of a caffeine molecule. Oxygen is red, carbon is blue-grey, nitrogen gree; hydrogens not shown. Drawn in Inkscape. 咖啡因分子 caffeine、chemical、chemistry、model、molecule、science 咖啡因、化學、化學、模型、分子、科學 資料來源:openclipart ( https://openclipart.org/ )