| Videos: 29 results |
Vapor Pressure: Drinking Bird
A novelty store "Drinking Bird" repeatedly dips is beak into a beaker of water and then bobs back to an upright position. Visible movement of a liquid in the bird's body accompanies the bobbing; the movement is caused by changing vapor pressure of the liquid due to different temperatures at the bird's head and the bird's body.
Liquids |
Phases / Phase Transitions / Diagrams
|
Boiling by Cooling
A flask contains water and water vapor at 100C. Each time ice water is poured over the outside of the flask, the water inside the flask boils. Although the temperature of the water in the flask has decreased, in each instance boiling is observed.
Gases |
Liquids |
Phases / Phase Transitions / Diagrams
|
Vapor Pressure: Molecular Size
The measurement of pressure exerted by a vapor is demonstrated using barometers. Vapor pressure varies with the strength of the intermolecular forces in the liquid.
Gases |
Liquids |
Noncovalent Interactions |
Phases / Phase Transitions / Diagrams |
Physical Properties
|
Vapor Pressure of a Mixture: Raoult's Law
The measurement of pressure exerted by a vapor is demonstrated using barometers. Vapor pressure varies with the strength of the intermolecular forces in the liquid.
In this section we will look at vapor pressure of mixtures. We can calculate the vapor pressure of a mixture using Raoult's law.
Gases |
Liquids |
Noncovalent Interactions |
Phases / Phase Transitions / Diagrams |
Physical Properties
|
Thermochromism: Mercury(II) Iodide
When red-orange Mercury(II) Iodide (HgI2) is heated, it undergoes a phase transition at 126oC to a pale yellow form. As the heated sample cools, it gradually returns to the original red-orange color.
Crystals / Crystallography |
Phases / Phase Transitions / Diagrams |
Physical Properties |
Solid State Chemistry |
Solids |
Descriptive Chemistry
|
Enthlapy-Thermodynamics
Reactions and demonstrations the explore thermodynamic concepts.
Precipitation / Solubility |
Solutions / Solvents |
Calorimetry / Thermochemistry |
Applications of Chemistry |
Acids / Bases |
Physical Properties |
Reactions |
Thermodynamics |
Gases |
Phases / Phase Transitions / Diagrams |
Water / Water Chemistry |
Liquids |
Solids |
pH |
Consumer Chemistry |
Kinetics |
Oxidation / Reduction
|
Phase Changes
By using a coolant at a temperature below the boiling point of the gases chlorine, bromine and iodine, the gases are condensed into liquid form.
Phases / Phase Transitions / Diagrams
|
Critical Point of Benzene
A sealed tube containing benzene liquid and vapor is heated. As the critical temperature is approached, the meniscus flattens. At the critical temperature the meniscus disappears, and separate liquid and vapor phases can no longer be detected.
Phases / Phase Transitions / Diagrams
|
Steam and Superheated Steam
When a gas burner heats the steam coil strongly, the steam becomes superheated and is at a high enough temperature to ignite a match and react quickly with steel wool
Gases |
Phases / Phase Transitions / Diagrams
|
Superconductivity
A pellet of 1-2-3 yttrium barium copper oxide (YBa2Cu3O7-x) is cooled with liquid nitrogen. A magnet placed above the pellet is levitated. At a higher temperature the magnet rests on the pellet, but cooling once again causes the magnet to rise. The levitated magnet is spun with plastic tweezers
Phases / Phase Transitions / Diagrams |
Superconductivity
|
Atmospheric Pressure
Atmospheric pressure is used to collapse large and small metal containers.
Phases / Phase Transitions / Diagrams |
Gases |
Atmospheric Chemistry
|
Vapor Pressure
Pressure exerted by vapor of several organic substances is demonstrated using barometers. Molecular models of the substances are shown.
Gases |
Phases / Phase Transitions / Diagrams |
Physical Properties
|
Liquefaction of Carbon Dioxide
Dry ice is placed into an acrylic plastic cylinder. A valve is closed and pressure in the cylinder increases. When the pressure reaches 350 kPa (50 psi) it stops increasing and liquid CO2 appears.
Equilibrium |
Phases / Phase Transitions / Diagrams |
Physical Properties
|
Solids-Liquids
Reactions and demonstrations exploring the properties of solids and liquids.
Solids |
Liquids
|
Solutions
Reactions and demonstrations exploring the concepts of solutions.
Noncovalent Interactions |
Physical Properties |
Precipitation / Solubility |
Solutions / Solvents |
Calorimetry / Thermochemistry |
Applications of Chemistry |
Acids / Bases |
Aqueous Solution Chemistry |
pH |
Conductivity |
Reactions |
Titration / Volumetric Analysis |
Liquids |
Solids |
Equilibrium |
Transport Properties
|
Scattering and Absorption of Light
The effects of passing light through a colloidal suspension of milk in water and through a solution of copper sulfate are shown.
Colloids |
Physical Properties |
Liquids
|
Viscosity of Liquids
The viscosities of water, 2-propanol (rubbing alcohol), ethylene glycol (antifreeze) and vegetable oil are compared. The viscosities of water, hexane, octane, 2,2,4-trimethylpentane and 1-pentanol are measured.
Liquids |
Physical Properties
|
Electrical Conductivity-Liquids
The conductivity of liquids are tested.
Conductivity |
Liquids |
Physical Properties
|
Simulation of Dislocations in Metals
An array of soap bubbles is used to simulate a close-packed arrangement of atoms in a metal crystal.
Metallic Bonding |
Metals |
Solids
|
Electrical Conductivity-Solids
The conductivity of various solids are tested.
Conductivity |
Solids |
Physical Properties
|
Sodium Chloride Crystal Cleavage
A knife is placed on a large sodium chloride crystal parallel to a cleavage plane. When the knife is tapped, the crystal breaks cleanly, creating two smaller crystals.
Crystals / Crystallography |
Ionic Bonding |
Solids
|
Measuring Relative Viscosity
The rate of flow of six different liquids through a Mohr pipet is measured.
Liquids |
Physical Properties |
Laboratory Equipment / Apparatus
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Paramagnetism: Nitrogen and Oxygen
A magnet is shown to strongly attract a pair of metal tongs. The magnet has no visible effect on liquid nitrogen, but when pale blue liquid oxygen is poured near the poles of the magnet, it shows definite attraction.
Magnetic Properties |
Atomic Properties / Structure |
Liquids
|
Ferrofluid
A magnet placed just below a dish containing ferrofluid generates an array of spikes in the fluid.
Liquids |
Magnetic Properties |
Metals |
Atomic Properties / Structure
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Plastic Sulfur
Yellow powdered sulfur is heated until it becomes molten and brown. At first it flows freely, but then it becomes very viscous. Upon further heating, the viscous sulfur flows freely again and ignites. The burning liquid sulfur is poured into a beaker of water. When removed from the water, the sulfur is rubbery and flexible.
Molecular Properties / Structure |
Physical Properties |
Solids
|
Heat Treatment of a Metal Bobby Pin
A bobby pin is subjected to various heat treatments.
Metallic Bonding |
Metals |
Solids |
Physical Properties
|
Piezoelectric Effect
Sounds accompany the discharges of electricity.
A piezoelectric crystal is connected to a light bulb. When the crystal is pressed, the light flashes.
Crystals / Crystallography |
Molecular Properties / Structure |
Solid State Chemistry |
Solids
|
Hardness of Solid Substances
The hardness of various solids are compared.
Covalent Bonding |
Nonmetals |
Physical Properties |
Solids |
Noncovalent Interactions
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Hardness of Solid Substances - Grinding
A number of metals and nonmetals are ground with a mortar and pestle. The nonmetals shown here are all soft (due to weak intermolecular forces), but the metals vary in hardness.
Covalent Bonding |
Nonmetals |
Physical Properties |
Solids |
Metallic Bonding |
Metals
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