Iodometric microgram determination of chromium(III) and (VI) by use of chemical amplification reactions.

A simple, rapid and sensitive method is described for the iodometric determination of microgram amounts of chromium(III), based on the oxidation of chromium(III) with periodate at pH 3.2, removal of the unreacted periodate by masking with molybdate and subsequent iodometric determination of the liberated iodate. Chromium(VI) can be determined by this method after prior reduction to chromium(III) with sodium sulphite. The method can also be used for the analysis of organochromium compounds.

Eugenol improvement due to aging. A laboratory appraisal.

The characteristics of eugenol for dental use appear to improve with age. Exposure to air and light causes certain chemical and physical changes, but the exact nature of the age improvement requires further elucidation.