an acid 土 H++a base HAc =H*+Ac H2PO-H*+HPO2 HPO-H*+PO NH-H*+NH3 [CH:NH3]*=H*+CH3NH2 [Fe(H2O)]*-H*+[Fe(OH)(H2O);]2* [Fe(OH)(H2O);]2*-H*+[Fe(OH)2(H2O)aT conjugate acid conjugate base an acid-base conjugate pair(共轭酸碱对)an acid H+ + a base + - HAc H + Ac - + - + 2 H2PO 4 H HPO 4 - + - + 3 4 2 HPO 4 H PO + + + NH 4 H NH 3 [ ] + + + CH 3NH 3 H CH 3NH 2 + + + + 2 2 5 3 [Fe(H 2O) 6 ] H [Fe(OH)(H O) ] + + + + 2 2 4 2 [Fe(OH)(H 2O) 5 ] H [Fe(OH) (H O) ] conjugate acid conjugate base an acid-base conjugate pair (共轭酸碱对)