Properties of the coordination compounds Experiment 13 Properties of the coordination compounds

Purposes 1. To observe the formation of coordination compounds and the distinguish between complex ions and simple ions. 2. To compare the stabilities of complex ions. 3. To know the relationship between the coordination equilibrium and the precipitation reaction, oxidation-reduction reaction and the acidities of solutions.

Principles complex ions complex compounds / coordination compounds chelates formation constant (Kf) / stability constant (Ks)

Procedure 1. The generation of coordination compounds Cu(OH)2 NH3 ·H2O Cu(OH)2 1ml CuSO4 NH3 ·H2O [Cu(NH3)4]2+

2. The distinguish between the complex ions and the simple ions ① KSCN [Fe(SCN)6)3-] 0.1M FeCl3 KSCN 0.1M K3[Fe(CN)6) ? NaOH ② NH3 ·H2O NH3 ·H2O NiSO4 Ni(OH)2 [Ni(NH3)4)]2+ NaOH Ni(OH)2 NiSO4

3. Compare the stabilities of complex ions NH3 ·H2O [Ag(NH3)2)]+ KI AgNO3 Na2S2O3 [Ag(S2O3)2)] 3-

4．The shifting of coordination equilibrium ① Ag+ + Cl- = AgCl ↓ + 2 NH3 ·H2O Cl- ? [Ag(NH3)2)]+ I- ?

② Fe3+ + 6F- ③ CCl4 [FeF6]3- I- CCl4 1d H2SO4 + 1d H2SO4 [Cu(NH3)4]2+ ↓

5．Shielding effect of ligands EDTA Pb(NO3)2 ? K2CrO4 ? Pb(NO3)2 H2O