CHEM101 Lecture Notes - Lecture 7: Intermolecular Force, Ice, Hydrogen Bond
Document Summary
Act between neighbouring molecules of the same type. Determine physical properties such as melting point, boiling point, viscosity, and solubility. Polar molecule align in solids and liquids so that the positive end of the dipole is near the negative end of another dipole. When h is either bonded to f,n, or o. H-bonding interactions are maximised when a more open structure is adopted hence lower density than water. Are there forces of attraction between nonpolar molecules. E. g hydrogen and helium can be condensed to liquids at low temperature, but are very weak. Due to the fact that electrons are continually moving, at any moment a dipole can exist for a moment in a molecule such as h2. Can induce another dipole in a second molecule. Short-lived and extremely weak dipole-dipole interactions result. Only possible intermolecular forces for nonpolar molecules. Size of atoms and their electron clouds. Elements bonded with hydrogen, with hydrogen usually being the more electronegative species.
