In this activity, learners discover that atoms and ions of different metals will change places. Learners place drops of copper sulfate solution onto a steel nail, then observe as the solution loses its blue color, and the steel nail becomes copper colored. This activity has been revised from original reaction system using silver nitrate solution and copper metal. The primary link is to new operating guide, and the original operating guide is also available. This activity is currently used in the Chemical Reactions Unit in OMSI's Chemistry Lab. Cost estimates are per 100 learners. For safety reasons, this activity should be conducted as a demonstration for younger audiences.