A.HCl B.NaCl C.Na2CO3 D.H2O
A.0.2mol•L-1NaAc/0.1mol•L-1Hac B.0.1mol•L-1NaAc/0.2mol•L-1HAc C.0.1mol•L-1NaAc/0.3mol•L-1Hac D.0.4mol•L-1NaAc/0.3mol•L-1HAc
A.4 B.7 C.10