What best describes a dilution series?

A dilution series is characterized by a stepwise dilution of a substance, which involves systematically reducing the concentration of a solute by adding a solvent in a sequential manner. This method allows for the preparation of a range of concentrations from a concentrated stock solution, facilitating various analytical techniques such as calibration curves, where different concentrations can be used to establish the relationship between concentration and response in measurements, such as absorbance in spectrophotometry.

By preparing a dilution series, researchers can observe changes in responses at varying concentrations, which is crucial for determining the limits of detection and quantification of the substance being studied. This method is fundamental in analytical chemistry because it ensures that samples fall within a measurable range, improving the accuracy and reliability of the analytical results.

In contrast, a single concentration does not provide the needed range for comparison, creating limitations for analytical assessments. While creating mixtures is a component of various laboratory processes, it does not specifically define a dilution series. Additionally, solid-phase extraction is a technique used for sample preparation, not related to the sequential dilution process that defines a dilution series.