Equilibrium Between Nitrogen Dioxide and Dinitrogen Tetroxide
Effect of Pressure on Melting Point of Ice
The Liquid Phase of Carbon Dioxide
Vapor Pressure of Pure Liquids
Getting Colder: Freezing-Point Depression
Getting Hotter: Boiling-Point Elevation by Nonvolatile Solutes
Osmotic Pressure of a Sugar Solution
Vapor Pressure Of Solutions: Raoult’s Law
Boiling Two Liquids at Room Temperature
Salting Out: Making Liquids Immiscible
Electrolysis of Potassium Iodide
Hydrogen Ion Concentration Cell
Acid-Base Properties of Amino Acids
Electrical Conductivity of Liquids and Solutions
Instrumental Recording of a Titration Curve
A Visual Demonstration of Raoult’s Law
A Visual Demonstration of Raoult’s Law
Two photos, each showing two capped test tubes with dark brown liquid appearing at the bottom of the tubes. In the left photo, each tube has an upper yellow layer and a lower brown layer. In the right photo, the left tube contains an upper yellow layer and a lower brown layer. The right tube’s upper and lower layers are yellow.
Description: The intensity of color of bromine vapor is reduced by placing a colorless volatile liquid into the same container.
Source: Journal of Chemical Education – Vol. 67
Year: 1990 Volume: 67 Page: 598
Keywords: Ideal solution, Raoult’s Law, Vapor pressure, Partial pressure, Bromine
Rating: 
Hazard: Medium
- Inhalation hazard
- Acute toxicity hazard
- Chemical burn hazard
- Skin corrosion hazard
- Serious eye damage
- Aquatic toxicity hazard
- Flammability hazard
Effectiveness: Good
- Results are observable with guidance
- Good connection from demo to course material
- Clear contrast between behavior of systems
- Time to results is medium
- Good reliability
Difficulty: High
- Careful manipulations required to avoid exposure to reagents
- Use of toxic reagents
- Multi-step procedure with variable results
- Demos in which a display is used
- Prior practice recommended
Safety Precautions:
- Perform in a well-ventilated area, downdraft hood preferred
- Gloves are required
- Eye protection is required
- Chemical spill reagents on hand- Sodium thiosulfate, 10% solution
- Use UL approved three-prong plug and outlet
- Prevent release of reagents to the environment
Class: Properties of Solutions, Physical Behavior of Gases, Partial Pressure
Division: General, Physical Chemistry
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