Homework SourseA 229 mL sample of 337 M trimethylamine is titrated with 316
A 22.9 mL sample of .337 M trimethylamine is titrated with .316 M hydrobromic acid. At the titration midpoint, the pH is? The answer is NOT 5.29
A 22.9 mL sample of .337 M trimethylamine is titrated with .316 M hydrobromic acid. At the titration midpoint, the pH is? The answer is NOT 5.29
Solution
at titration mid point
50% of trimethyl amine convert to mmonium sat. so at mid point
[amine] = [salt]
pOH = pKb + log [salt] / [amine]
as [salt] = [amine]
log [salt] / [amine] = 0
pOH = pKb (pKb = 4.19 for trimethyl amine)
pOH = 4.19
pH = 14 - 4.19
pH = 9.81
