1 / 51

Complex Ions

Complex ions are formed when positively charged central metal ions coordinate with several ligands, which can be anions or neutral molecules. The central metal is usually a transition metal, such as Cu²⁺ or Ni²⁺. Ligands can be unidentate, bidentate, or polydentate, influencing the coordination number and geometric structure of the complex. Naming conventions are systematic, prioritizing cations over anions and ligands are named before the metal. Understanding the bonding (coordinate covalent bonds) and geometric isomers helps to grasp the complexity of these compounds in coordination chemistry.

zohar
Download Presentation

Complex Ions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Complex Ions

  2. Complex Ion • An ion formed when a positive central element binds with multiple ions or polar molecules

  3. Complex Ion • The central element is almost always a positively charged metal

  4. Describe or define a Complex Ion

  5. Anion • Negatively charged ion

  6. Cation • Positively charged ion

  7. Metal Ion Examples • Cu+2 Cu+ Au+ • Ag+ Zn+2 Ni+2 • Pt+2 Co+2 Al+3

  8. Ligands • The negative ions or polar molecules bound by the central element in a complex ion

  9. Ligand Examples • Cl- F- H2O • NH3 CN- Br- • NO O2 OH-

  10. Polydentate Ligands • Ligands that can bind to more than one point

  11. Bidentate Ligands • Ligands that can bind to two points in a complex ion

  12. Bidentate Examples • H2N-CH2-CH2-NH2 • -O2C-CO2-

  13. Tridentate Ligands • Ligands that can bind to three points in a complex ion

  14. Tridentate Examples • H2-C-COO- • HO-C-COO- • H2-C-COO-

  15. Chelates • Polydentate ligands that bind to metal ions in solution

  16. Coordination Number • The number of points in which ligands bind to the central element in a complex ion

  17. Coordinate Covalent Bond • Covalent bonds in which both electrons involved are donated by one atom

  18. Complex Ions • The bonds formed in a complex ion are coordinate covalent bonds

  19. Coordination Complex • A complex ion and its counter ion

  20. Complex Ions • The bonds formed in a complex ion are coordinate covalent bonds

  21. Complex Ion • Because of the type bonding, they are sometimes called coordinate complexes

  22. 1) Name cations before anions

  23. Naming Complexes • 2) Name ligands before metal in the complex ion

  24. 2) Naming Ligands • a) give neutral compds normal names except:

  25. H2O aqua • NH3 amine • CO carbonyl • NO nitrosyl

  26. 2) Naming Ligands • b) change -ide endings to -o for all anions

  27. 2) Naming Ligands • d) use geometric prefixes for monodentate ligands

  28. 2) Naming Ligands • e) use bis- for 2 & tris- for 3 polydentate ligands

  29. 3) Naming Metal • a) use the normal name if the complex ion is (+)

  30. 3) Naming Metal • b) make the metal ending -ate if the complex ion is (-)

  31. 3) Naming Metal • d) use Roman numerals in () to indicate metal ox #

  32. Name the Following: • [Pt(NH3)4]Cl2 • [Co(H2O)2Cl4]-2 • [Cu(H2O)2(en)2]I2

  33. Predict # of isomers of each: • [Pt(NH3)4 Cl2] [Co(H2O)3Cl3]

  34. Complex Ion Shapes • 2-linear • 4-tetrahedral or sq pl • 6-octahedral

  35. Geometric Isomers • Square planar vs tetrahedral • cis vs trans

  36. Geometric Isomers • Bunched octa- • T-shaped octa- • bis: cis vs trans

  37. Optical Isomers • Tri-bis mirror images

  38. Field Strength • CN- > NO2- > en > NH3 > NCS- > H2O > F- > Cl-

  39. Field Strength • CN- is strong field • Cl- is weak field

  40. Field Strength • Determines d-level splitting or Do(splitting energy)

  41. Field Strength • Large Do yields low spin or diamagnetic compds

  42. Field Strength • Small Do yields high spin or paramagnetic compds

  43. [Pt(NH3)2I4]-2 • Determine: • Name, shape, & possible isomerism

  44. [Co(NH3)6]+3 yellow [Co(NH3)5NCS]+2 orange [Co(NH3)5H2O]+2 red [Co(NH3)5Cl]+2 purple t-[Co(NH3)4Cl2]+1 green

  45. Complex Ion Equilibria Cu+2 + 4 NH3 [Cu(NH3)4]+2 [Cu(NH3)4]+2 [Cu+2][NH3]4 Kf =

  46. Calculate the ratio of [Cu+2]/ [Cu(NH3)4]+2 when Cu+2 is added to a 0.10 M NH3 solution:Kf = 2.0 x 1012

  47. Common Ion Equilibria • The larger the Kf, the more likely the complex will form

  48. Common Ion Equilibria • Kf for [Ag(NH3)2]+1 • = 1.7 x 107 • Kf for [Ag(CN)2]-1 • = 2.0 x 1020

  49. Common Ion Equilibria • Kf for [M(NH3)2]+2 • = 1.7 x 107 • Kf for [M(CN)4]-2 • = 2.0 x 1020

  50. Common Ion Equilibria CN- will replace NH3 in the complex with silver

More Related