At the middle school level, it is not necessary for students to learn about electron orbitals. This information is offered so that it is clearer to you why electrons are often shown in pairs in energy ...

Activation energy is the minimum energy needed for ‘successful collisions’ where atoms within the reactants rearrange to form products. It can be represented on an energy level diagram. The ...

Energy-level diagram of Cr3+ in corundum, showing pertinent processes. Full size image. Fig. 2. Emission spectrum of ruby : a, low-power excitation; b, high-power excitation.