In: Chemistry
Consider the titration of 60.0 mL of 0.0400 M C6H5NH2 (a weak base; Kb = 4.30e-10) with 0.100 M HCl. Calculate the pH after the following volumes of titrant have been added: a) 45.6 mL
no of moles of C6H5NH2 = molarity * volume in L
= 0.04*0.06 = 0.0024moles
no of moles of HCl = molarity * volume in L
= 0.1*0.0456 = 0.00456moles
C6H5NH2 + HCl ----------------> C6H5NH3Cl
I 0.0024 0.00456 0
excess no of moles of HCl = 0.00456-0.0024 = 0.00216moles
[H+] = no of moles of HCl/total volume in L
= 0.00216/0.1056 = 0.02045 M
PH = -log[H+]
= -log0.02045 = 1.6893