Inadmissibility of the “AnalaR” method for the determination of metallic zinc in zinc oxide
Abstract
A chemical method for the quantitative determination of non-stoicheiometric zinc in zinc oxide, previously published by the author, has been incorrectly applied by AnalaR Standards Limited to the determination of free metallic zinc in zinc oxide. It is shown that, unless the free metal is extremely finely divided, large amounts can be present in the zinc oxide without being recorded in the analysis. Even with particle diameters as small as 1 µm, only 3 per cent. or less of the metallic zinc is detected by the method.