This demonstration extracts liquid
oxygen from a cryogenic mixture
collected through condensation using a small neodymium magnet. In
a simple and inexpensive procedure, small amounts of liquid oxygen
can be safely collected and observed. Students directly witness the
collection of this cryogenic mixture over a 30 minute time period
and the subsequent immediate removal of small quantities (ca. <1
mL) of liquid oxygen as a consequence of its paramagnetic properties.
Several techniques are suggested that allow the efficient handling
and display of the magnet used for the extraction. Although framed
here in the context of an introductory chemistry or general chemistry
course, these procedures can easily be adapted to general-interest
audiences or more advanced undergraduate chemistry courses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.