A polarographic study of the saturated straight‐chain alpha‐bromo acids (acetic to caprylic) indicates a similar pattern of behavior for all, involving fission of the carbon‐ halogen bond and conversion to the corresponding acid. As the chain length increases, the ease of reduction increases at all pH values, with the one exception that bromopropionic acid in the alkaline region is more difficultly reducible than bromobutyric acid.Maxima effects found with the acids can apparently be ascribed to the colloidal behavior of the acids upon dilution with buffers in which the reducible acid has a lower solubility than in pure water.The effects of ethanol on half‐wave potential, E 1/2, and diffusion current, i d. have been investigated with representative members of the series. In the alkaline region E 1/2 becomes more negative and i d decreases as the alcohol content increases. The evidence in the acid region, though not entirely conclusive, indicates the reverse effect with regard to E 1/2.The behavior of the 2‐bromo‐n‐alkanoic acids does not follow the rule that the ease of polarographic reduction increases with substitution of more electronegative groups. The influences of structure and inductive effect are considered relative to the ease of carbon‐halogen bond fission. The apparent differences between the present work and that reported by others is discussed.

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Atomic absorption spectroscopy is one of several analytical tools which can be applied to the determination of less than 20 ppm quantities of copper and nickel in tea. A rapid and accurate atomic absorption method is described which is sensitive to these elements at the levels of interest. After the decomposition of organic matter by oxidation with nitric and perchloric acids, or by dry ashing, a solution is obtained which contains only a few major elements. An average matrix composition is determined and synthetic standards for copper and nickel which are free of potential interferences are prepared for a calibration curve. Tea leaves have been analyzed chemically and by X-ray and optical emission spectroscopy in order to evaluate the accuracy of the atomic absorption method. The average of 50 determinations gives a mean of 11 ppm nickel and 32 ppm copper with standard deviations of ±1.6 σ and 1.8 σ, respectively. The method should be applicable to most organic material.