This laboratory uses ion chromatography (IC) to quantify phosphate (PO4-3) and nitrate (NO3-) ions in surface water in order to teach green, environmental and analytical chemistry to a general chemistry audience. The topics covered include:
fertilizers in the environments,
eutrophication, and nitrous oxide (N2O) as a greenhouse gas;
12 principles, and the
Presidential Green Chemistry Awards Entries; and
analytical chemistry topics:
volumetric analysis with
standard solutions and
Students use a buret and common volumetric glassware to create standard curves of nitrate or phosphate from a provided stock solution. The samples are run on an ion chromatograph (IC) between laboratory periods, data work-up involves calculation of the standard concentrations, a calibration curve and a linear regression. We use an in-house EXCEL template to create a calibration curve for students though they acquire this skill before the first semester is over. The laboratory is intentionally simplified for our very new students though the material could be easily expanded for use in a number of upper-level applications.
The laboratory PDF file includes a robust set of introductory materials including, implementation ideas and supporting web sites along with a chemical and equipment list, pre-laboratory worksheets (on green chemistry and analytical chemistry) and details for the laboratory exercise. Additional resources include PowerPoint teaching slides (as a PDF).
Summary prepared March 2012 by Professor Liz Gron at Hendrix College.
Gron, L. Nitrate and/or Phosphate Ions in Surface Water, Chemistry, Hendrix College, 2012