CH 102 Lecture Notes - Lecture 2: Coordination Number, Cubic Crystal System, Triple Point

• School: University of Alabama
• Department: Chemistry
• Course: CH 102
• Professor: Martin Bakker

Document Summary

Phase diagrams describe the different states and state changes that occur at various temperature/pressure conditions: regions represent states, lines represent state changes. The liquid/gas line is the vapor pressure curve. On the line, both phases exist simultaneously: points. The critical point is the farthest point on the vapor pressure curve. Triple point is the temperature/pressure condition in which all three states exist simultaneously. For most substances, the freezing point increases as pressure increases. Crystalline solids are orderly geometric structures whose lattice points are occupied by atoms, ions, or molecules. Constructive interference adds to the amplitude of the electromagnetic wave, whereas destructive interference subtracts from the wave"s amplitude: bragg"s law allows scientists to determine the distance between layers of atoms or molecules in a crystal lattice. When allowed to cool slowly, the particles in a liquid will arrange themselves to give the maximum attractive forces: therefore, they minimize the energy, the result will generally be a crystalline solid.