Chemsheets AS006 (Electron arrangement)

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Presentation transcript:

Chemsheets AS006 (Electron arrangement) 21/04/2017 www.CHEMSHEETS.co.uk INORGANIC COMPLEXES © www.chemsheets.co.uk A2 042 20-Jul-12

Metal aqua ions Substitution by Cl- Hydrolysis Substitution by NH3 Metal aqua ions + OH- Summary 1 Metal aqua ions + NH3 Chelate effect Metal aqua ions + CO32- Redox Summary 2 © www.chemsheets.co.uk A2 042 20-Jul-12

METAL AQUA IONS © www.chemsheets.co.uk A2 042 20-Jul-12

METAL AQUA IONS e.g.[Cu(H2O)6]2+ © www.chemsheets.co.uk A2 042 20-Jul-12

METAL AQUA IONS complex colour [Cu(H2O)6]2+ blue [Co(H2O)6]2+ pink [Fe(H2O)6]2+ green [V(H2O)6]2+ [Cr(H2O)6]3+ violet* [Fe(H2O)6]3+ pale violet** [Al(H2O)6]3+ colourless © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

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© www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

REACTIONS Hydrolysis O-H bond in H2O ligand breaks Substitution M-ligand bond breaks Redox change in oxidation state of M © www.chemsheets.co.uk A2 042 20-Jul-12

HYDROLYSIS © www.chemsheets.co.uk A2 042 20-Jul-12

HYDROLYSIS OF Mn+(aq)

HYDROLYSIS OF Mn+(aq) M3+ more acidic due to: M3+ smaller and greater charge than M2+ so O-H bond breaks more easily.

HYDROLYSIS OF M2+(aq) [M(H2O)6]2+  [M(H2O)5(OH)]+ + H+ [M(H2O)5(OH)]+  [M(H2O)4(OH)2] + H+ [M(H2O)4(OH)2]  [M(H2O)3(OH)3]- + H+ [M(H2O)3(OH)3]-  [M(H2O)2(OH)4]2- + H+ [M(H2O)2(OH)4]2-  [M(H2O)(OH)5]3- + H+ [M(H2O)(OH)5]3-  [M(OH)6]4- + H+

HYDROLYSIS OF M3+(aq) [M(H2O)6]3+  [M(H2O)5(OH)]2+ + H+ [M(H2O)5(OH)]2+  [M(H2O)4(OH)2]+ + H+ [M(H2O)4(OH)2]+  [M(H2O)3(OH)3] + H+ [M(H2O)3(OH)3]  [M(H2O)2(OH)4]- + H+ [M(H2O)2(OH)4]-  [M(H2O)(OH)5]2- + H+ [M(H2O)(OH)5]2-  [M(OH)6]3- + H+

METAL AQUA IONS + OH-

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]2+ + 2 OH- → [M(H2O)4(OH)2] + 2 H2O M2+(aq) + 2 OH-(aq) → M(OH)2(s) [Cu(H2O)6]2+ + 2 OH- → [Cu(H2O)4(OH)2] + 2 H2O Cu2+(aq) + 2 OH-(aq) → Cu(OH)2(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]2+ + 2 OH- → [M(H2O)4(OH)2] + 2 H2O M2+(aq) + 2 OH-(aq) → M(OH)2(s) [Co(H2O)6]2+ + 2 OH- → [Co(H2O)4(OH)2] + 2 H2O Co2+(aq) + 2 OH-(aq) → Co(OH)2(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]2+ + 2 OH- → [M(H2O)4(OH)2] + 2 H2O M2+(aq) + 2 OH-(aq) → M(OH)2(s) [Fe(H2O)6]2+ + 2 OH- → [Fe(H2O)4(OH)2] + 2 H2O Fe2+(aq) + 2 OH-(aq) → Fe(OH)2(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]3+ + 3 OH- → [M(H2O)3(OH)3] + 3 H2O M3+(aq) + 3 OH-(aq) → M(OH)3(s) [Al(H2O)6]3+ + 3 OH- → [Al(H2O)3(OH)3] + 3 H2O Al3+(aq) + 3 OH-(aq) → Al(OH)3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]3+ + 3 OH- → [M(H2O)3(OH)3] + 3 H2O M3+(aq) + 3 OH-(aq) → M(OH)3(s) [Fe(H2O)6]3+ + 3 OH- → [Fe(H2O)3(OH)3] + 3 H2O Fe3+(aq) + 3 OH-(aq) → Fe(OH)3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + OH- [M(H2O)6]3+ + 3 OH- → [M(H2O)3(OH)3] + 3 H2O M3+(aq) + 3 OH-(aq) → M(OH)3(s) [Cr(H2O)6]3+ + 3 OH- → [Cr(H2O)3(OH)3] + 3 H2O Cr3+(aq) + 3 OH-(aq) → Cr(OH)3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

AMPHOTERIC NATURE Amphoteric = reacts with acids and bases XS H+ XS OH- [Cu(H2O)6]2+ [Cu(OH)2] [Fe(H2O)6]2+ [Fe(OH)2] [Co(H2O)6]2+ [Co(OH)2] [Fe(H2O)6]3+ [Fe(OH)3] [Cr(H2O)6]3+ [Cr(OH)3] [Cr(OH)6]3- [Al(H2O)6]3+ [Al(OH)3] [Al(OH)4]- © www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + XS OH- [Cr(H2O)3(OH)3]  [Cr(OH)6]3- + 3 OH- + 3 H2O Cr(OH)3(s) → [Cr(OH)63-](aq) + 3 OH-(aq) [Al(H2O)3(OH)3]  [Al(H2O)2(OH)4]- + OH- + H2O Al(OH)3(s) → [Al(OH)4-](aq) + OH-(aq) © www.chemsheets.co.uk A2 042 20-Jul-12

METAL AQUA IONS + NH3 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]2+ + 2 NH3 → [M(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M2+(aq) + 2 OH-(aq) → M(OH)2 [Cu(H2O)6]2+ + 2 NH3 → [Cu(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Cu2+(aq) + 2 OH-(aq) → Cu(OH)2 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]2+ + 2 NH3 → [M(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M2+(aq) + 2 OH-(aq) → M(OH)2 [Fe(H2O)6]2+ + 2 NH3 → [Fe(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Fe2+(aq) + 2 OH-(aq) → Fe(OH)2 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]2+ + 2 NH3 → [M(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M2+(aq) + 2 OH-(aq) → M(OH)2 [Co(H2O)6]2+ + 2 NH3 → [Co(H2O)4(OH)2] + 2 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Co2+(aq) + 2 OH-(aq) → Co(OH)2 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]3+ + 3 NH3 → [M(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M3+(aq) + 3 OH-(aq) → M(OH)3 [Cr(H2O)6]3+ + 3 NH3 → [Cr(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Cr3+(aq) + 3 OH-(aq) → Cr(OH)3 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]3+ + 3 NH3 → [M(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M3+(aq) + 3 OH-(aq) → M(OH)3 [Fe(H2O)6]3+ + 3 NH3 → [Fe(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Fe3+(aq) + 3 OH-(aq) → Fe(OH)3 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + NH3 [M(H2O)6]3+ + 3 NH3 → [M(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) M3+(aq) + 3 OH-(aq) → M(OH)3 [Al(H2O)6]3+ + 3 NH3 → [Al(H2O)3(OH)3] + 3 NH4+ NH3(aq) + H+(aq) → NH4+(aq) Al3+(aq) + 3 OH-(aq) → Al(OH)3 © www.chemsheets.co.uk A2 042 20-Jul-12

METAL AQUA IONS + CO32- © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- [M(H2O)6]2+ + CO32- → [M(H2O)6]CO3 M2+(aq) + CO32-(aq) → MCO3(s) [Cu(H2O)6]2+ + CO32- → [Cu(H2O)6]CO3 Cu2+(aq) + CO32-(aq) → CuCO3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- [M(H2O)6]2+ + CO32- → [M(H2O)6]CO3 M2+(aq) + CO32-(aq) → MCO3(s) [Co(H2O)6]2+ + CO32- → [Co(H2O)6]CO3 Co2+(aq) + CO32-(aq) → CoCO3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- [M(H2O)6]2+ + CO32- → [M(H2O)6]CO3 M2+(aq) + CO32-(aq) → MCO3(s) [Fe(H2O)6]2+ + CO32- → [Fe(H2O)6]CO3 Fe2+(aq) + CO32-(aq) → FeCO3(s) © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- 2 H+ + CO32- → H2O + CO2 [M(H2O)6]3+ provides 3 H+ ions 2 [M(H2O)6]3+ + 3 CO32- → 2 [M(H2O)3(OH)3] + 3 H2O + 3 CO2 2 [Cr(H2O)6]3+ + 3 CO32- → 2 [Cr(H2O)3(OH)3] + 3 H2O + 3 CO2 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- 2 H+ + CO32- → H2O + CO2 [M(H2O)6]3+ provides 3 H+ ions 2 [M(H2O)6]3+ + 3 CO32- → 2 [M(H2O)3(OH)3] + 3 H2O + 3 CO2 2 [Fe(H2O)6]3+ + 3 CO32- → 2 [Fe(H2O)3(OH)3] + 3 H2O + 3 CO2 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

AQUA IONS + CO32- 2 H+ + CO32- → H2O + CO2 [M(H2O)6]3+ provides 3 H+ ions 2 [M(H2O)6]3+ + 3 CO32- → 2 [M(H2O)3(OH)3] + 3 H2O + 3 CO2 2 [Al(H2O)6]3+ + 3 CO32- → 2 [Al(H2O)3(OH)3] + 3 H2O + 3 CO2 © www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION BY Cl- © www.chemsheets.co.uk A2 042 20-Jul-12

[Co(H2O)6]2+ + 4 Cl-  [CoCl4]2- + 6 H2O © www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by larger ligands Cl- bigger than O of H2O – only four Cl-’s fit around Mn+ H Cl- O H © www.chemsheets.co.uk A2 042 20-Jul-12

[Cu(H2O)6]2+ + 4 Cl- → [CuCl4]2- + 6 H2O © www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION BY NH3 © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ [Cu(H2O)6]2+ + 4 NH3 → [Cu(NH3)4(H2O)2]2+ + 4 H2O © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ [Cu(H2O)6]2+ + 4 NH3 → [Cu(NH3)4(H2O)2]2+ + 4 H2O [Fe(H2O)6]2+ © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ [Cu(H2O)6]2+ + 4 NH3 → [Cu(NH3)4(H2O)2]2+ + 4 H2O [Fe(H2O)6]2+ [Fe(H2O)6]3+ © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ [Cu(H2O)6]2+ + 4 NH3 → [Cu(NH3)4(H2O)2]2+ + 4 H2O [Fe(H2O)6]2+ [Fe(H2O)6]3+ [Cr(H2O)6]3+ + 6 NH3 → [Cr(NH3)6]3+ + 6 H2O © www.chemsheets.co.uk A2 042 20-Jul-12

© www.chemsheets.co.uk A2 042 20-Jul-12

SUBSTITUTION by similar sized ligands [Co(H2O)6]2+ + 6 NH3 → [Co(NH3)6]2+ + 6 H2O air [Co(NH3)6]2+ [Cu(H2O)6]2+ + 4 NH3 → [Cu(NH3)4(H2O)2]2+ + 4 H2O [Fe(H2O)6]2+ [Fe(H2O)6]3+ [Cr(H2O)6]3+ + 6 NH3 → [Cr(NH3)6]3+ + 6 H2O [Al(H2O)6]3+ © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY 1 © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY [M(H2O)6]3+ M(OH)3 + CO2 M(OH)3 [Cr(NH3)6]3+ [Cr(OH)6]3- OH- / NH3 H+ XS NH3 M(OH)3 [Cr(NH3)6]3+ XS OH- [Cr(OH)6]3- [Al(OH)4]- © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY [M(H2O)6]2+ MCO3 M(OH)2 [Co(NH3)6]2+ [Cu(NH3)4(H2O)2]2+ OH- / NH3 H+ XS NH3 M(OH)2 [Co(NH3)6]2+ [Cu(NH3)4(H2O)2]2+ XS OH- No reaction © www.chemsheets.co.uk A2 042 20-Jul-12

CHELATE EFFECT © www.chemsheets.co.uk A2 042 20-Jul-12

THE CHELATE EFFECT [Cr(H2O)6]3+ + 3 en → [Cr(en)3]3+ + 6 H2O 4 particles → 7 particles [Cr(H2O)6]3+ + EDTA4- → [Cr(EDTA)]- + 6 H2O 2 particles → 7 particles Small H in substitution reactions. Big increase in entropy (large +ve S). Products are thermodynamically more stable than reactants – known as the “chelate effect” © www.chemsheets.co.uk A2 042 20-Jul-12

REDOX REACTIONS © www.chemsheets.co.uk A2 042 20-Jul-12

REDUCTION OF Cr(+6) 2 CrO42- + 2 H+  Cr2O72- + H2O oxidation state yellow Cr +6 orange oxidation state species colour Cr +6 Cr2O72- orange © www.chemsheets.co.uk A2 042 20-Jul-12

REDUCTION OF Cr(+6) 2 CrO42- + 2 H+  Cr2O72- + H2O oxidation state yellow Cr +6 orange oxidation state species colour Cr +6 Cr2O72- orange Cr +3 Cr3+ [Cr(H2O)6]3+ green © www.chemsheets.co.uk A2 042 20-Jul-12

REDUCTION OF Cr(+6) 2 CrO42- + 2 H+  Cr2O72- + H2O oxidation state yellow Cr +6 orange oxidation state species colour Cr +6 Cr2O72- orange Cr +3 Cr3+ [Cr(H2O)6]3+ green Cr +2 Cr2+ [Cr(H2O)6]2+ blue Reduced by Zn/H+ from Cr +6 → +3 → +2 © www.chemsheets.co.uk A2 042 20-Jul-12

Cr(+3) – OXIDATION IN ALKALINE CONDITIONS Easier to oxidise (take electrons) from –ve species. Easier to reduce (add electrons) to +ve species. e.g. Cr(+3) in acidic conditions in alkaline conditions in very alkaline conditions [Cr(H2O)6]3+ [Cr(OH)3] [Cr(OH)6]3- H2O2 / OH- Zn / HCl CrO42- Cr(+6) [Cr(H2O)6]2+ Cr(+2) © www.chemsheets.co.uk A2 042 20-Jul-12

Cr(+3) – OXIDATION IN ALKALINE CONDITIONS CrO42-+ 4 H2O + 3 e-  Cr(OH)3 + 5 OH- E = -0.13 V Cr2O72- + 14 H+ + 6 e-  2 Cr3+ + 7 H2O E = +1.33 V © www.chemsheets.co.uk A2 042 20-Jul-12

Co(+2) – OXIDATION IN ALKALINE CONDITIONS air Co(OH)2 Co(OH)3 Co(+2) Co(+3) Made from Co2+ in alkaline conditions air [Co(NH3)6]2+ [Co(NH3)6]3+ Co(+2) Co(+3) Made from Co2+ in alkaline (NH3) conditions © www.chemsheets.co.uk A2 042 20-Jul-12

M(OH)2 – OXIDATION IN ALKALINE CONDITIONS air Co(OH)2 Co(OH)3 Co(+2) Co(+3) air Fe(OH)2 Fe(OH)3 Fe(+2) Fe(+3) Fe(OH)3 + e-  Fe(OH)2 + OH- E = -0.56 V Fe3+ + e-  Fe2+ E = +0.77 V © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY 2 © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY [M(H2O)6]3+ M(OH)3 [Cr(OH)6]3- CrO42- [Al(OH)4]- [Cr(NH3)6]3+ XS OH- OH- / NH3 XS NH3 [M(H2O)6]3+ M(OH)3 [Cr(NH3)6]3+ H+ [Cr(H2O)6]3+ Cr(OH)3 [Fe(H2O)6]3+ Fe(OH)3 [Al(H2O)6]3+ Al(OH)3 CO32- + CO2 © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY [M(H2O)6]2+ M(OH)2 [CuCl4]2- [CoCl4]2- [Cu(H2O)2(NH3)4]2+ XS OH- Cl- OH- / NH3 XS NH3 [M(H2O)6]2+ M(OH)2 [Cu(H2O)2(NH3)4]2+ H+ [Cu(H2O)6]2+ Cu(OH)2 [Co(NH3)6]2+ [Co(H2O)6]2+ Co(OH)2 air [Fe(H2O)6]2+ Fe(OH)2 CO32- air [Co(NH3)6]3+ CuCO3 Co(OH)3 CoCO3 Fe(OH)3 FeCO3 © www.chemsheets.co.uk A2 042 20-Jul-12

SUMMARY [M(H2O)6]2+ MCO3 M(OH)2 [Co(NH3)6]2+ [Cu(NH3)4(H2O)2]2+ OH- / NH3 H+ XS NH3 M(OH)2 [Co(NH3)6]2+ [Cu(NH3)4(H2O)2]2+ XS OH- No reaction © www.chemsheets.co.uk A2 042 20-Jul-12