Which of the following mixtures has the higher pH? (a) Equal volumes of 0.10 M HCN and 0.10 M NaOH (b) Equal volumes of 0.10 M HClO4 and 0.10 M NaOH

Acid-base reactions involve the transfer of protons (H+) between reactants. In this context, strong acids like HClO4 completely dissociate in solution, while weak acids like HCN only partially dissociate. The strength of the acid and base in the mixtures will determine the resulting pH after they react.

The pH scale measures the acidity or basicity of a solution, ranging from 0 (very acidic) to 14 (very basic), with 7 being neutral. A higher pH indicates a more basic solution, which is relevant when comparing the outcomes of the mixtures in the question. Understanding how to calculate pH from concentrations of acids and bases is crucial.

Neutralization is the reaction between an acid and a base, resulting in the formation of water and a salt. The extent of neutralization affects the final pH of the solution. In the mixtures presented, the amount of strong base (NaOH) will determine how much of the acid is neutralized, influencing the final pH of each mixture.