Gases

Surprising Shrinking Styrofoam Stick: Using the Gas Laws to Get a Square Peg into a Round Hole

Polystyrene foam sticks with a square or rectangular profile will not fit into a round target hole (e.g., the opening of a soda bottle) at room temperature. However, they do contract sufficiently in contact with liquid nitrogen to fit into the hole and produce a simple demonstration of Charles’s Law. Many other polymer foams do not shrink under these conditions, but still provide opportunities to discuss and explore their structure and chemistry.

Gas Laws with Daniel Radoff

Gas Laws are an essential and easily accessible area of chemistry to understand. They can be an excellent foothold into the inner workings of chemistry. On December 9th, 2021, Daniel Radoff shared his unit covering gas laws in this ChemBasics Talk. You can view a recording of his presentation and access materials he has suggested.

A Highly-Scaffolded Activity for Helping Students Generate Exam Review Questions and See Patterns in Quantitative Problem Solving

Helping students develop abstract understanding is a universal goal. This article describes an activity that involves students developing and then solving novel quantitative chemistry problems following a MadLibsTM style framework.

Real vs Ideal - Do Students "Get It"?

Allowing students to confront the failure of a model and then helping them construct a new or slightly modified model to account for new observations is at the heart of the process of science. Ben Meacham shares one approach that can be deployed with a variation of depth, making it attainable for anyone learning about chemistry.

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.