This episode introduces titration, a technique used to determine an unknown concentration (analyte) using a solution of known concentration (titrant). The focus is the strong acid–strong base titration, where reactants fully dissociate. The equivalence point is reached when moles of H+ equal moles of OH-, resulting in a neutral pH of 7.0. Beyond this point, the pH rises sharply. Calculations rely on stoichiometry (moles) to determine the required volume and subsequent solution pH.