CHEM 112 1 nd Edition Lecture 5 Outline of Last Lecture I. Liquid-Gas Phase Changes II. Boiling Point III. Liquid-Solid Phase Changes IV. Solid-Gas Phase Changes V. Heating & Cooling Curves Outline of Current Lecture I. Intermolecular forces II. Properties of Liquids III. Properties of Solids Current Lecture  Intermolecular forces: The attractive forces between molecules o London Dispersion Forces  Relative boiling points tell us about intermolecular force strength  The stronger the forces, the higher the temperature needed to overcome them o Dipole Dipole forces  One of the elements polarizes the other  attractive forces between the positive end of one polar molecule and the negative end of another polar molecule These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. o Hydrogen Bonding  Occurs with Nitrogen, Oxygen, and Fluoride.  Hydrogen bonding is the strongest thing that holds DNA helixes together  Hydrogen bonding in H20 causes ice to be less dense than the liquid state  Properties of Liquids  Vapor pre