Student Exploration: Reaction Energy Directions: Follow the instructions to go through the simulation. Respond to the questions and prompts in the orange boxes. Vocabulary: calorimeter, chemical bond, endothermic, enthalpy, exothermic, Hess’s law Prior Knowledge Questions (Do these BEFORE using the Gizmo.) Two magnets are stuck together. What might you have to do to get them to separate? Suppose you held two magnets a short distance apart, then let go. What would happen? Think about the magnets in terms of energy. In which case do you increase the potential energy of the magnets? In which case do you increase the kinetic energy of the magnets? Gizmo Warm-up Just like magnets, atoms of different elements are attracted together to form chemical bonds. Breaking these bonds requires energy. When a new bond forms, energy is released and temperatures rise. In the Reaction Energy Gizmo, you will explore how the energy of chemical bonding relates to temperature changes that occur during chemical reactions. To begin, check that Reaction 1 and Forward are selected. In this reaction, hydrogen (H2) and oxygen (O2) react to form water (H2O). The reaction takes place inside a device called a calorimeter. Inside the calorimeter, a small chamber holds the reactants. The rest of the calorimeter is filled with water. Click Play (). What happens? How does the temperature change?