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Condensed Matter

  1. Crystal Properties
    • Giant Vibrating Crystal Styrofoam spheres linked by springs in a 3x3x3 cubic lattice
    • Atomic and Molecular Crystal Models Wooden, plastic, and Styrofoam models for show-n-tell. (m) (T)
    • Buckyball. Truncate an icosohedron to produce a Buckminister Fullerene...this is accompanied by a soccer ball and a C60 model. (m) (T)
    • OHP Crystal Defects Simulator Ball bearings on shaking table show crystal defects, impurities, and dislocations. (m) (T++) ***
    • Crystal Growth and Recession Observation of ice crystal growth under microscope; growth/recession controlled by dry ice boundary. (s) (T++) **
    • Crystal Growth in Castings. A hot casting is cooled rapidly to show the progression of crystal growth. (s) (T++)
    • Dilatancy of Deformation Balloon filled with sand and ink; any compression results in increase in volume due to deformation of close packing. (s) (T++) **
    • Cleaving of Sodium Chloride. Cleave down crystal boundaries of rock salt. (s) (T)
    • Periodic Potential Balls in a frame simulating the repeating potential wells of a lattice. (m) (T) **
    • Laue Optical Analog. 2-Dim interfernce pattern as optical analog of x-ray diffraction; spinning the grating simulates polycrystaline ring patterns. (l) (T)
    • Liquid Crystals Liquid crystal sheets, OHP display, and calculator or watch, among others, are available for show-n-tell. (s) (T) ***
    • Molecular Size. Molecular size is determinded by means of a Langmuir trough. (m) (T++)
    • Glass Transition. Caramelized sugar assumes glasslike characteristics when rapidly cooled. (m) (T+)
    • Supersaturation and Crystallization Supersaturated solution of sodium acetate in beaker; crystallization triggered by seeding. (s) (T+++) **
    • BCC to FCC The microcystaline structure of a steel wire changes from body-centered-cubic to face-centered-cubic as it is heated to red-hot. (m) (T+) ***
    • Change of Volume with State CO2 and He balloons dipped in liquid nitrogen. (m) (T+) **
    • Sublimation of CO2. Solid dry ice turns directly into gaseous state. (m) (T)
    • Solid, Liquid, Gaseous CO2. Observation of phase changes with corresponding pressure changes. (s) (T+)
    • PVT Surfaces. Three-dimensional plaster model of PVT relationships. (m) (T)
  2. Mechanical Properties
    • Creep of Lead Lead rod subjected to tensile load. (m) (T+)
    • Fracture Strength of Chalk Chalk rod subjected to tensile and compressive loads. (m) (T+) *
    • Surface Treatment of Glass Comparison of breaking strength of microscope slides before and after treatment with acid. (s) (T+++) ***
    • Balogna Bottle and Rupert's Drops. Stressed glass shatters catastrophically with a little help. (s) (T+)
    • Young's Modulus. Stretching of long wire with load. (l) (T+)
    • Work Hardening and Annealing. Annealed brass rod is hardened by bending. (m) (T+)
    • Strength of Copper Wire. Annealed and drawn copper wire are compared. (m) (T++)
    • Solid Properties at Low Temperature Change of properties of objects after immersion in liquid nitrogen. (m) (T+) ***
    • Chinese "Faith" Bell Unlike the lead bell which rings when cold, this copper alloy bell exhibits the opposite effect of temperature on vibrational damping. (m) (T)
    • Rubber Elasticity. Unlike most other materials. rubber contracts when heated. (s) (T+)
  3. Electromagnetic Properties
    • Hall Effect. The Hall voltage of a semiconductor is measured as a function of applied magnetic field. (l) (T++)
    • Photoelectric Cell. Photoelectric effect demonstrated with common "solar cell". (m) (T)
    • Photoresistivity. Photoconductivity of CdS cell moved through the continuous spectrum. (m) (T+)
    • Insulator or Conductor? Resistance of glass vs. temperature. (s/m) (T++)
    • Superconductivity Meissner Effect suspension of magnet above superconducting disc. (s) (T+) ***