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Determination of the Ionization Constants of Weak AcidsLone Star College Kingwood20000 Kingwood Dr. Kingwood TX 77339ABSTRACT:A weak acid is an acid that ispartially dissociated into its ion in an aqueoussolution or even water. Our objective was todetermine the ionization constant for acetic acid(HC2H3O2), and the constant for maleic acid,(H2C4H2O4). We followed the lab procedure and didexactly as the the manual instructed us to do, suchas using the drop counter, the pH probe calibratedto a pH of 2.00 and a pH of 10.00, (etc). We came toa conclusion that the ionization constant for aceticacid resulted at a pH of 8.35, which we predictedcorrectly would be a base.We also determined theionization constants for maleic acid, which resultedat a pH of 3.94 for the first point and 9.74 at thesecond equivalence point and would be a base.IntroductionThis lab was done to determine the ionizationconstant, ka, for acetic acid (HC2H3O2) and theionization constants, ka1and ka2, for maleic acid(H2C4H2O4).The Henderson-Hasselbach equation is utilized whenthe solution contains a weak acid alongside its saltin a relatively large quantity in relation to theoccurring ionization.pH=pKa+log[salt][acid]where pKa=−logkaka=ionizationconstant for weakacid[salt]=concentrationmolLof salt of conjugatebase o[acid]=concentrationmolLof weak acidInitially, no salt is present in acetic acid, thoughwhen titrated with NaOH, the acetic acid graduallyconverts to its conjugate base, NaC2H3O2and water