This demonstration builds upon the commonly performed liquefaction of air not only to show the presence of nitrogen and oxygen, but also the presence of two other components, carbon dioxide and water. Several extensions are suggested: one to show boiling point elevation in solution and another to show the elevation of both boiling point and sublimation point with pressure. No special apparatus is required permitting presentations to audiences in a variety of settings. These demonstrations give the opportunity to discuss properties of gases, solution chemistry, and phase equilibria. Special emphasis is given to the conceptual explanations of the processes involved.
More Information
Citation
Oliver-Hoyo, Maria; Switzer, William L., III. J. Chem. Educ.2005 82 251.
Keywords
Demonstrations; Gases; General Chemistry; Qualitative Analysis
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