The economic demonstrator: prepare it once, use it many times. V. liquid–liquid phase transition phenomena

A simple and economic way of conducing demonstration experiments about liquid–liquid phase transitions is presented and discussed. Pairs of liquids are sealed in a series of ampoules and each ampoule is put in a beaker filled with either ice or hot water. Depending on the nature of the components mixed, the system can become homogeneous or heterogeneous. Three kinds of systems are discussed: a system with upper critical temperature, with lower critical temperature, and a system with both upper and lower critical temperature.