Abstract

Differential-pulse anodic stripping voltammetry at a mercury microelectrode is applied to determine labile and total zinc, cadmium, lead and copper in samples of rain and sea water. The low ohmic drop associated with microelectrodes permits reliable measurements in rain water without addition of supporting electrolyte. The values found in a typical sample were 0.95 μg l −1 Cu, 0.38 μg l −1 Pb, 0.01 μg l −1 Cd and 0.95 μg l −1 Zn, with relative standard deviations in the range 4–18%. The small effects of organic matter at microelectrodes, compared with those at a hanging mercury drop electrode, allow sensitive and reliable measurements of labile metals in surface sea water. Total metal concentrations are determined after acidification to pH 1.5 with hydrochloric acid. The results are compared with those obtained with atomic absorption spectrometry and with differential-pulse anodic stripping voltammetry at conventional mercury electrodes. Satisfactory results were obtained for a reference sea water.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call