The Chemical EducatorISSN: 1430-4171 (electronic version) Abstract Volume 10
Issue 5 (2005) pp x371x-377 Do Nanoparticles Have Equilibrium Constants?Thomas Manning,* Justin Bennett, Lori Hardin, and Kim Harris Department of Chemistry, Valdosta State University,
Valdosta, Georgia 31698, tmanning@valdosta.edu Published online: 26 September 2005 Abstract. In this exercise three systems that fall under the broad envelope of nanoparticles are examined by aqueous-phase titrations. First, we examine the acidity curve of copper oxide nanoparticles (CuO) and monitor it with a pH and copper-ion selective electrode. The titration curve of CuO, which dissolves in acidic medium, is compared to the curve of insoluble titanium dioxide nanoparticles suspended in the aqueous phase. Second, we compare the titration curves of ZnO, CuO, Fe2O3, Ce2O3, Al2O3, and TiO2 nanoparticles suspended in solution and titrated with an acid. The ZnO and CuO curves indicate that the addition of an acid causes them to dissolve, the Fe2O3 and Ce2O3 titration curves suggest that the suspended nanoparticles protonate, and the TiO2 and Al2O3 data show little reaction with the acid. Lastly, we analyze ozonated single-wall carbon nanotubes and salmon sperm ss-DNA and look for an interaction between the two systems. These three systems are presented not as individual laboratory exercises but are used to demonstrate that various aspects of nanoscience can be implemented as a first- or second-year chemistry laboratory exercise in a safe and economical manner.
Key Words: Laboratories and Demonstrations; general chemistry; analytic chemistry; nano (*) Corresponding author. (E-mail: tmanning@valdosta.edu) Article in PDF format (352 KB) HTML format Supporting Materials:
Issue date: October 1, 2005 |