Evaporation of water on duck's head cools vapor inside causing low pressure, etc.
Dippy Duck is a small heat engine consisting of a hollow glass barbell with opposite ends able to seesaw about a knife edge pivot. One end of the barbell is...
A 5-gallon bottle containing air and water vapor is slightly pressurized; a sudden release of the pressure cools the vapor, forming a cloud.
The bottle is a heavy Pyrex carboy with tooled mouth. A one-holed rubber stopper fits the mouth and is air-tight. A...
CO2 and He balloons in liquid nitrogen.
Cooling a gas causes a proportional decrease in volume with the drop in absolute temperature. A gas such as helium, which remains close to ideal at low temperatures, shows a four-fold decrease in volume...
Observation of phase changes with corresponding pressure changes.
A two ml. plastic microcentrifuge vial and a small shop vise are used together to melt dry ice.
Wear safety glasses for this demo. The vial can explode, or shoot out of the vice, from the...
Three-dimensional plaster model of PVT relationships. Other versions exist, one by J.C.Maxwell and shown here.
Images of the plaster phase surface of water.
Room temperature water boils in an evacuated bell jar and then freezes due to rapid surface evaporation.
The microcystaline structure of a steel wire changes from body-centered-cubic to face-centered-cubic as it is heated to red-hot.
Iron atoms are arranged in a body-centered cubic pattern (BCC) up to 1180 K. Above this temperature it makes a...
The demonstration shows density fluctuations in liquids. These fluctuations are particularly spectacular near critical points. A binary fluid mixture of methanol (29% by weight) and cyclohexane (71%) becomes opalescent when heated up to its...
Hot fluid rises, cool fluid sinks. Here is a desktop convection cell modeling the processes in the atmosphere, oceans or stellar interiors.
The currents are set up in rheoscopic fluid[1] (basically minute aluminum flakes in...
Here we set up a convection cycle, where we heat part of a fluid; it expands, rises, then cools and sinks. A two dimensional model for real convection cycles in the atmosphere, oceans or stellar interiors.
The convection cell...
Dropping bag containing lead turns gravitational potential energy to heat.
A demonstration of the conversion of gravitational potential energy to heat energy. A bag of lead shot, repeatedly dropped to the ground, will heat up.
L...
Compression of gas within bicycle pump heats gas; alternatively, syringe PV=nRT (w/ Mac TC read-out).
An adiabatic process is one where no heat enters or leaves a system. Here we compress a gas adiabatically inside a bicycle pump. The work...
