Equilibrium Between Nitrogen Dioxide and Dinitrogen Tetroxide
Effect of Pressure on Melting Point of Ice
The Liquid Phase of Carbon Dioxide
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
Model of Osmotic Pressure
Description: Lentils and beans are used to represent molecules of two different sizes. The screen between them is small enough only to let the lentils through to the other side. Initially the “fluid” levels are equal. Shaking the container mixes the two “molecules” together. Soon, the “fluid” levels are different on the two sides of the screen.
Source: Journal of Chemical Education – Vol. 76
Year: 1999 Vol: 76 Page: 64
Keywords: Lentils, Fluid levels, Osmosis, Membrane
Rating: 
Hazard: Low
- Model or simulation
Effectiveness: Average
- Mild effects are seen by audience
- Good reliability
- Time to results is low
- Good connection from demo to course material
Difficulty: Low
- Simple manipulations for most to perform
- Simple procedures
Safety Precautions:
- Eye protection required
Class: Simulations, Properties of Solutions, Equilibrium of Chemical Systems, Osmosis
Division: General, Physical Chemistry
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