Transition Metals Flashcards
Define ligand.
A atom, ion or molecule that donates a lone pair to form a dative bond with a metal ion
Define co-ordinate number.
The number of co-ordinate bonds formed with a metal ion
Define ligand substitution.
When one ligand replaces another
Why did student use a lower concentration for the titre?
To obtain a larger titre to reduce uncertainty
Explain why CO is toxic
- Haemoglobin contains Fe ions that bond datively to O2
- CO2 replaces O2 via ligand substitution
- CO2 forms stronger bonds with Fe than O2
What are the characteristics of a transition metal?
- Forms coloured compounds
- Incomplete d level in sub-ions
- Variable oxidation states
- Catalytic activity
- Forms complex ions
Why is zinc not a transition metal?
It contains a full d sub shell when it becomes a Zn ion
Why is Sc not a transition metal?
It contains an empty d sub shell when it becomes a Sc ion
Why can ligand substitution by HCl cause a change in co-ordinate number?
Whilst NH3 and H2O are similar in size, Cl- is bigger! Therefore the co-ordinate number can change from 6 to 4
Cis-trans isomerism can only occur in…
Octahedral + Square Planar (Not Tetrahedral)
Optical Isomerism
Present when there are bidentate ligands in octahedral complexes forming non super-imposable images
Control Solution:
[Cu(H2O)6]2+
Fe2+
Fe3+
Mn2+
Cr3+
- Blue
- Pale Green
- Yellow
- Pale Pink
- Violet if all ligands are H2O, green if acidified (Cl- or SO42- ligand)
+ NaOH
Cu
[Fe(OH)2(H2O)4]
Fe3+
Mn2+
Cr3+
- Blue
- Green
- Orange Brown
- Light Brown
- Grey Green (Excess Dark Green)
+ aqueous NH3
[Cu(OH)2(H2O)4]
Fe2+
Fe3+
Mn2+
Cr3+
- Blue
- Green
- Orange Brown
- Light Brown
- Grey Green
+ Conc HCl
[CuCl4]2-
Fe3+
Yellow Solution
