A.F->CN->HCOO- B.CN->HCOO->F- C.CN->F->HCOO- D.HCOO->F->CN-
A.6.10 B.5.50 C.6.50 D.5.70
A.CN-[KθaHCN)=6.2×10-10] B.S2-[Kθa1(H2S)=1.3×10-7,Kθa2(H2S)=7.1×10-15] C.CH3COO-[Kθa(CH3COOH)=1.8×10-5] D.F-[Kθa(HF)=3.5×10-4]