Carbon dioxide absorbers: An engaging context for stoichiometry in the general chemistry laboratory

CHED 183

Thomas M. Ticich, tticich@centenary.edu, Department of Chemistry, Centenary College of Louisiana, 2911 Centenary Boulevard, P.O. Box 41188, Sheveport, LA 71134
I have developed a simple and direct method for measuring the uptake of carbon dioxide by lithium hydroxide suitable for the general chemistry laboratory. The reaction has been used for decades to remove this gas from enclosed living spaces, such as spacecraft. The mass ratio of carbon dioxide to lithium hydroxide obtained from this static method compares favorably with that in the literature using a more complex constant flow method. Students are motivated to determine the actual yield of the reaction, which is far from complete, to predict the amount of lithium hydroxide required for a space mission of a particular duration. In addition, they determine the sign of the enthalpy change of the reaction and confirm the identity of the carbonate product. The method also works well with ethanolamine as the carbon dioxide absorber so that students can compare its performance characteristics with lithium hydroxide.
 

General Posters
7:30 PM-9:30 PM, Sunday, March 25, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Sci-Mix

Division of Chemical Education

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007