A.硫酸溶液 B.鹽酸 C.氯化鐵溶液 D.氨水
A.C21H31COOH B.C31H41COOH C.C22H22COOH D.C22H43COOH
A.pH=2的稀硫酸 B.pH=2的甲酸溶液 C.0.010mol•L-1鹽酸 D.0.010mol•L-1的苯酚溶液