CH3COOH + NaOH => CH3COONa + H2O
mCH3COOH = 120x10/100 = 12 (g)
=> nCH3COOH = m/M = 12/60 = 0.2 (mol)
mNaOH = 200x10/100 = 20 (g)
=> nNaOH = m/M = 20/40 = 0.5 (mol)
Lập tỉ số: NaOH > CH3COOH (0.5> 0.2) => NaOH dư
==> n NaOH pứ = 0.2 (mol)
mdd sau pứ = 120 + 200 = 320 (g)
mCH3COOH = n.M = 0.2 x 82 = 16.4 (g)
C% = 16.4 x 100 / 320 = 5.125 %