Abstract
Simple method for the determination of zinc oxide in the sprayed zinc coating is not yet provided, though it is quite important in the inspection of quality of coating. The authors' effort is, therefore, mainly focussed to obtain methods for practical use.
First, we tried to estimate the oxide content from the volume of hydrogen gas evolved when the coating was dipped in acid solution. The volume changed sensibly as was expected, with the change of oxide content. After many tests, it was found that, this method could be used for practice if the temperature of the gas was regularly controlled by proper apparatus.
Second, the coating was tried to dissolve in the potassium iodide solution containing iodine. By this treatment, not only the metal, but also a small amount of oxide are dissolved, which makes the determination not simple. Thus, it seems that, for practice, the first method is better than the second with respect to operation, accuracy and cost of analysis.
