"CHEM"opera is an opera blended with demonstrations of chemical reactions. It has been produced and performed twice by chemistry undergraduate students at Hallym University in South Korea. It aims to demonstrate interesting chemical reactions to chemistry students, children and the public and to facilitate their understanding of the role of chemistry in reducing the problems of global warming. The chemical reactions portrayed in "CHEM"opera have proven to excite both young children and chemistry students. It could serve as a tool to arouse the audience's interest in chemistry and to deliver an important message to them.