Demonstration Of The Color And Paramagnetism Of Liquid Oxygen In The Classroom Using A Simple Handmade Liquefier

In this work, it will be demonstrated that a metal cone constructed by folding a thin copper disk can be employed as a simple apparatus to condense ambient air to obtain liquid oxygen. This handmade liquefier is so simple that even undergraduate students can construct it by themselves. By using this liquefier, a demonstration for observing the blue color and the magnetic property of liquid oxygen can be carried out in the chemistry class, and it can be effective for expanding students' elementary knowledge of quantum chemistry and molecular spectroscopy.