Boyle’s Law and the Mass of a Textbook
Effect of Pressure on the Size of a Balloon
Egg in a Flask – Thermal Decrease in Molar Volume
Flow of Gas Through a Porous Cup
Rate of Diffusion: The Ammonium Chloride Ring
Boltzmann: Digital Simulation of Kinetic Molecular Theory
Boyle’s Law and the Monster Marshmallow
PhET Simulation of Gas Behavior
Effect of Pressure Differences on a Balloon in a Flask
Extinguishing Candles With Carbon Dioxide
A Metal Bar to Demonstrate One Atmosphere
Relation of Gas Pressure and Temperature
Transport of Carbon Dioxide Through a Soap Film
Digital Molecular Theory Simulator
Professor in a Bag
Description: The lecturer places a large clear plastic bag containing a mixture of approximately 80% helium and 20% oxygen over his/her head. The lecturer’s voice rises for several minutes.
Source: UW Card Catalog
Year: N/A Vol: N/A Page: N/A
Keywords: Helium, Oxygen, Plastic bag, Voice, Frequency, RMS velocity, Boltzmann
Ratings: 
Hazard: Some
- Asphyxiation hazard
- Inert gas in use
- Oxidizer
Effectiveness: Good
- Strong effects are seen by audience
- Low failure rate
- Time to results is low
- Good connection from demo to course material
Difficulty: Medium
- Simple procedures
- Simple manipulations for most to perform
- Sequential manipulations
- Demos at non-standard conditions
Safety Precautions:
- Ensure oxygen is placed in bag to avoid asphyxiation
- Eye protection required
- Perform in a well-ventilated area
- Handle pressurized gas with caution
Class: Gas Laws, Physical Chemistry, Molecular Properties
Division: General
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