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an ecobotanist separates the components of a tropical bark extract by chromatography. she discovers a large proportion of quinidine, a dextrorotatory isomer of quinine used for control of arrhythmic heartbeat. quinidine has two basic nitrogens (kb1 = 4.0 10-6 and kb2 = 1.0 10-10). to measure the concentration, she carries out a titration. because of the low solubility of quinidine, she first protonates both nitrogens with excess hcl and titrates the acidified solution with standardized base. a 31.35 mg sample of quinidine (m = 324.41 gmol) is acidified with 6.55 ml of 0.150 m hcl? a) how many ml of 0.0152 m naoh are needed to titrate the excess hcl? ___ml b) how many additional milliliters of titrant are needed to reach the first equivalence point of quinidine dihydrochloride? ____ml c)what is the ph at the first equivalent point?
