demonstrations

The Carbon Dioxide Spiral Staircase

The demonstration where CO2 is generated and used to snuff out a candle in an aquarium or other container is well known. This article describes a dramatic variation on these demonstrations that allows for discussion of such topics as the ideal gas law, densities of different gases, gas density changes with temperature, miscibility, and viscosity. The device described is easily and inexpensively produced and stored. The demonstration is large scale and works well for classrooms and community outreach events. 

Organic Chemistry and Tree Fruit: The Control of Ethylene-Induced Ripening of Fruit in Cold Storage Warehouses

Ethylene, C2H4, a volatile plant hormone stimulates fruit ripening and is also released during ripening. This post explains the role of ethylene in ripening and presents how the chemical identity of the ethylene scavenger used to suppress premature ripening during storage was determined.