2 Different States of Matter Solid state - iceLiquid state - waterGas state - water vapor
3 Intermolecular Forces Intermolecular forces are forces between molecules.Intramolecular forces hold atoms together in a molecule.Intermolecular vs Intramolecular41 kJ to vaporize 1 mole of water (inter)930 kJ to break all O-H bonds in 1 mole of water (intra)“Measure” of intermolecular forceboiling pointmelting pointDHvapDHfusDHsubGenerally, intermolecular forces are much weaker than intramolecular forces.
4 Intermolecular Forces Dipole-Dipole Forces: Attractive and repulsive forces between polar moleculessolidliquid
5 Intermolecular Forces Hydrogen Bond: a special dipole-dipole interaction between the hydrogen atom in a polar N-H, O-H, or F-H bond and an electronegative O, N, or F atom.AH…BorA & B are N, O, or F
6 Intermolecular Forces Dispersion Forces: Attractive forces that arise as a result of temporary dipoles induced in atoms or molecules
7 Dispersion Forces among Nonpolar Molecules separated Cl2 moleculesinstantaneous dipoles
8 Intermolecular Forces Polarizability is the ease with which the electron distribution in the atom or molecule can be distorted.Polarizability increases with:greater number of electronsmore diffuse electron cloudDispersion forces usually increase with molar mass.
9 Intermolecular Forces What type(s) of intermolecular forces exist between each of the following molecules?CH4CH4 is nonpolar: dispersion forces.SOSO2SO2 is a polar molecule: dipole-dipole forces. There are also dispersion forces between SO2 molecules.HFHF is a polar molecule: dipole-dipole forces. Hydrogen is bounded to F. Hydrogen bonds exist. There are also dispersion forces between HBr molecules.
10 Structures and Types of Solids A crystalline solid possesses rigid and long-range order. In a crystalline solid, atoms, molecules or ions occupy specific (predictable) positions.An amorphous solid does not possess a well-defined arrangement and long-range molecular order.A unit cell is the basic repeating structural unit of a crystalline solid.latticepointUnit CellUnit cells in 3 dimensions
17 Metallic Crystals Lattice points occupied by metal atoms Held together by metallic bondsSoft to hard, low to high melting pointGood conductors of heat and electricitynucleus &inner shell e-mobile “sea”of e-
26 Chemistry In Action: High-Temperature Superconductors
27 AcknowledgmentSome images, animation, and material have been taken from the following sources:Chemistry, Zumdahl, Steven S.; Zumdahl, Susan A.; Houghton Mifflin Co., 6th Ed., 2003; supplements for the instructorGeneral Chemistry: The Essential Concepts, Chang, Raymon; McGraw-Hill Co. Inc., 4th Ed., 2005; supplements for the instructorPrinciples of General Chemistry, Silberberg, Martin; McGraw-Hill Co. Inc., 1st Ed., 2006; supplements for the instructor