Question

Calculeaza ph sol obtinute prin amestecarea a 15 mL sol HCl cu PH=1 si 35mL sol KOH 0,05M

Answer 1

HCl - A.T
[HCl] = C = [H3O+] = 10^-pH = 10^-1 M

n acid = 10^-1 × 15×10^-3 = 15×10^-4 moli

KOH - B.T
[KOH] = C = [OH] = 10^-pOH = 10^-0,05 = 0,891 M
n baza = 0,891×35×10^-3 = 0,0311 moli

KOH + HCl => KCl + H2O

n baza exces = 0,0311-0,0015 = 0,0296 moli

Cf = n baza exces /Vsf = 0,0296/0,05 = 0,593M

pOH = 10^-0,593 = 3,925
pH = 10