CEM 141 Lecture Notes - Lecture 25: Photon, Atomic Orbital
Document Summary
Absorption of a photon will promote an electron to a higher energy level. It immediately falls back down emitting a photon the metal shines(but not in the dark why not?) The metal interacts with light of many wavelengths, so the metal appears white or colorless (silvery) Requires energy in order to overcome attractions between molecules, energy comes from the surroundings. Releases energy because intermolecular attractions (between the molecules) are being formed, energy goes to the surroundings. When a substance melts, the interactions between the particles have to be overcome so that they can move relative to each other (that"s what allows a liquid to flow). The magnitude of the melting point and boiling point provides an estimate of the strength of the attractive interactions between particles. Discrete materials have a lower melting and boiling point than continuous materials. Strong (requires a lot of energy to break) Caused by attraction of electrons from one atom to nuclei from another atom.
