For the 6th grade students colorimetric tests, we are using the LaMotte Urban Water Quality Test Kit, available from Amazon and Acorn Naturalist.
To help the students perform the tests, we developed a worksheet and slideshow based on the instruction manual that comes with the kit.
The kit is easy to use, results in exciting color changes for positive results, and takes only about 5 minutes per test. The 40-mL water samples collected by the 6th graders are suitable for about 5 of the tests included in the kit.
For the instrumental analysis students' lab, we are analyzing the water samples on a Thermo Iris II Inductively Coupled Plasma Atomic Emission Spectroscopy instrument (ICP-AES). 19-element and 7-element standards were obtained from CPI International and diluted in 2% nitric acid to create a series of standards: 100, 10, 1, 0.1, 0.01 ppm.