Method Of Va Research Articles

Determination of Reaction Rates by the Use of Cubic Spline Interpolation

The differential method of van't Hoff is a powerful method for kinetic data analysis if accurate rates of reaction can be found. Differentiation methods reported in the literature are inadequate, particularly when applied to data which is unequally spaced or which is subject to random error. A need is therefore expressed for a general numerical method of differentiation which can be readily applied in kinetic analysis. This paper suggests the use of the cubic spline, an interpolation method which overcomes the difficulties of other methods and gives exceptionally accurate derivatives. The theory of the cubic spline, its properties, and uses are discussed. Its application to experimental data is demonstrated and its performance is quantitatively compared with better known but less accurate methods.

Interferences in the measurement of arsenic by the method of va?�k and ?edivec

In the measurement of arsenic by the method ofVasak andSedivec, different wavelengths have been used to measure the concentration of the arsenic diethyldithiocarbamate. Such differences may be explained by the possible presence of silver nitrate in the silver salt solution. The absorbance should be measured at 522 nm when the salt is properly purified.