Question #635c0

1 Answer
May 20, 2015

pH =4.56
The partial neutralization of acetic acid by sodium hydroxide leaves 0.0015 moles of acid and produces 0.001 moles of acetate.
The final solution is a buffer of acetic acid and acetate.
Final concentration of acetic acid (AcOHAcOH) =0.1 M *15/350.1M1535
=0.0428 M
Final concentration of (OH^-)(OH) = acetateion(AcO^-AcO)=0.1M*10/350.1M1035=0.0286 M
From the Henderson-Hasselbach equation:
pH=pKa+log ((Ac^-)/(HAc))pH=pKa+log(AcHAc)
pH=-log1.8*10^-5log1.8105 + log (0.0287/0.0428)log(0.02870.0428) = 4.74-0.17 = 4.56