Question

Part A When titrated with a 0.1198 M solution of sodium hydroxide, a 58.00 mL solution of an unknown polyprotic acid required 20.15 mL to reach the first equivalence point. Calculate the molar concentration of the unknown acid. O A¢ * R O ? Submit Request Answer Part B The titration curve was found to have three equivalence points. What volume of the sodium hydroxide solution was necessary to fully titrate the unknown acid solution? IVO ADD A O O ? Submit Request Answer

Answer 1

Part A : molar concentration of unknown acid = 0.04162 M

Part B : volume of NaOH required = 60.45 mL

Explanation

Part A :

concentration NaOH = 0.1198 M

volume NaOH = 20.15 mL

moles NaOH = (concentration NaOH) * (volume NaOH)

moles NaOH = (0.1198 M) * (20.15 mL)

moles NaOH = 2.414 mmol

moles acid present = 2.414 mmol

concentration of acid = (moles acid present) / (volume of acid)

concentration of acid = (2.414 mmol) / (58.00 mL)

concentration of acid = 0.04162 M