Which technique would one use to determine the concentration of a solution?

Titration is the technique used to determine the concentration of a solution. This process involves the gradual addition of a solution of known concentration (the titrant) to a solution of unknown concentration (the analyte) until the reaction reaches its endpoint, which can often be indicated by a color change or a pH shift. Through this method, one can accurately calculate the concentration of the unknown solution based on the volume of titrant used and its concentration, applying stoichiometric relationships from the balanced chemical equation for the reaction.

In contrast, the other techniques mentioned serve different purposes. Filtration is used to separate solid particles from liquids or gases and does not provide information about concentration. Distillation is primarily a separation technique based on differences in boiling points and is not typically used for quantifying concentration directly. Centrifugation separates components of a mixture based on density but does not measure concentration. Therefore, titration stands out as the clear choice for determining solution concentration.