In this paper, we present CheMO, a system for tangible chemistry experiments where users can interact with Mixed Object (MO) instruments that consist of a graspable physical part in the real world and a digital part in a virtual world. When used for an experiment, MO instruments enable users to employ tangible interaction methods inherited from real experience and to be given digital information similar to a physical expression arising from an actual experiment. The goal of our research is to enhance the sense of reality in a virtual experiment and to enable users to learn experimental procedures effectively and easily.