CHEM 0110 Chapter Notes - Chapter 11: Amorphous Solid, Non-Stoichiometric Compound, Covalent Bond
Document Summary
Gases: compressible fluids, composed of molecule or single atoms in constant random motion through mostly empty space. Fluid: individual molecules can move easily relative to one another. Liquids: relatively incompressible fluids: constant random motion, but more packed, so less free space. Lack of empty space explains why a liquid is incompressible, Particles (atoms, molecules, or ions) exist in close contact and do not move but oscillate or vibrate about fixed sites. Gases usually follow pv=nrt, but to account for extreme conditions use van der waals: (p +n^2a/v^2)(v-nb)=nrt. a=magnitude of intermolecular forces, b=depends on relative size of the molecules. Can"t make such a simple equation for liquids and solids because the volume of the molecules in their container is not negligible, and neither are their interactions because they"re more compact. But ice has high vapor pressure, so in winter, even if temp still below freezing, snow disappears because goes directly from ice to vapor.
