Charge of the Analyte and Ion Pair Reagent

The influence of the charge of the analyte ion on retention when the mobile phase concentration of the ion pair reagent varies can be understood from eqn [6]. When zA = + 1 and zB = — 1, the equation predicts that in a ln kcB vs ln cA plot the slope of the straight line is equal to 1/2 and when zB = zA =— 1 it is equal to — 1/2. Examples of experimental data for these two cases are shown in Figure 3.

For multiple charged ion pair reagents, the non-linearity of the adsorption isotherm becomes more pronounced than for monocharged reagents. Quantitatively, this is described in eqns [4]-[6] through the value for zA; when zA = + 2 eqn [6] predicts that the slope of the ln kcB vs ln cA plot is 2/5 for a negatively mono-charged analyte ion and 4/5 for a di-charged ion. An example is shown in Figure 4 where the di-charged hexamethonium bromide ion is used as ion pair reagent. The solid lines in the figure corresponds to the theoretically predicted slope.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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