Question

A 50 ml sample of .150M Ch3CooH is titrations with .150 M NaOh solution. Calculate the ph after the following volumes of base have been added: 49 ml, 51ml

Answer 1

CH3COOH + NaOH --> CH3COONa + H2O
millimols CH3COOH = 50 x 0.150 = ?
millimols NaOH = 49 x 0.150 = ?
mmols CH3COOH left = the difference.
M CH3COOH = mmols/total mL = ?
Then convert to pH.

Answer 2

for 49 ml: pH=2.8
for 51 ml: pH=11.17