6.2.3 Shapes of Complex Ions Flashcards
1
Q
What does the shape of complex ions depend on?
A
- Size of ligands
- Number of coordinate bonds
2
Q
What are linear complex ions like
A
- Ligands form 2 coordinate bonds
- 180 degrees
- Eg. Cu (I) or Ag (I) with NH3
3
Q
What are tetrahedral complex ions like
A
- 4 coordinate bonds
- 4 Cl ligands often form this shape
- Often forms tetrahedral structures with larger ligands
- 109.5 degrees bond angle
4
Q
What are square planar complex ions like
A
- 4 coordinate bonds
- CN- ligands do form this
- 90 degree bond angles
- Can display cis-trans isomerism
5
Q
What are octahedral complex ions like
A
- 6 coordinate bonds
- Can be with small, monodentate ligands such as H2O, NH3 or OH- or thiocyanate ions
- Expresses EZ Isomerism
- Or with 3 bidentate ligands
- Expresses optical isomerism
6
Q
How can geometric isomerism be seen in complex ions?
A
- No double bonds
- But square planar and octahedral complexes can display cis-trans isomerism
- 2 pairs of different ligands required
- Eg. Cis Platin
7
Q
What is cis platin?
A
- Square planar complex
- Beneficial medical effects by binding to DNA in cancer cells
8
Q
What do octahedral cis and trans isomers look like if I had to draw them?
A
9
Q
How can optical isomerism be seen in complex ions?
A
- Octahedral complexes
- With bidentate ligands
- Forms 2 non-superimposable mirror images of each other
10
Q
What shape does [Ag(NH3)2] + form? How is it used?
A
- Linear complex
- Used in tollens reagent
