A lab and demonstration was done to show how the production of heat during a chemical reaction can be used to produce something like a hand warmer. Iron fillings, sodium chloride and an absorbing material were measured out on a balance and placed into a plastic sandwich bag. When allowed to mix, the reaction produces heat which can be used to warm the hands in a cold environment. The reaction of the iron with oxygen in the bag and salt as a catalyst , with the formation or iron oxide was explained. Back in the classroom, the development of the Bohr atom model was undertaken, showing how it advanced the theory of Rutherford, and placed electrons in specific orbits or energy levels