Periodicity Of The D Block Flashcards
What’s the order of transition metals left to right?
Titanium
Vanadium
Chromium
Manganese
Iron
Cobalt
Nickel
Copper
What is the highest attainable oxidation state of series 1 TMs?
Reaches a peak at Mn(VII) - then decreases as Zeff increases
What’s the most common oxidation state of Ti?
4+
Why does Ti(II) not exist for long?
Because it is strongly reducing, d2 metal ion
Which 1st series TM ion is oxidising in solution?
Vanadium(V)
Becomes V(IV) - most common
What’s the most common oxidation state of V?
V(IV)
What’s the most common oxidation state of Cr?
Cr(III)
What’s the most common oxidation state of Mn?
Mn(II)
What’s the most common oxidation state of Fe?
Fe(II) and Fe(III)
What’s the most common oxidation state of Co?
Co(II) and Co(III)
What’s the most common oxidation state of Ni?
Ni(II)
What’s the most common oxidation state of Cu?
Cu(I) and Cu(II)
What properties do Cr(VI) and Mn(VII) exhibit?
Strong oxidising agents - often used in organic chemistry (CrO3) oxidise alcohols and ([MnO4]-) methyl units to carb. acids.
How is Fe(VI) made, what is its structure?
Made by IO4- oxidation of Fe(III) in pH 14 solution
Only one complex, [FeO4]2- (tetrahedral)
Why is it very rare to attain Co(IV)?
Because Co(III) is low-spin d6 which is hard to disrupt due to its stability
Why is nickel’s highest oxidation state Ni(IV)?
Because it is a low-spin d6 metal ion - gaining stability, more common than Co(IV)
What is the highest oxidation state of Cu?
Cu(III) a d8 metal ion - due to steric and electronic repulsions
What’re common properties of Copper complexes?
Most are diamagnetic, square planar complexes
Which is more stable, Cu(I) or Cu(II)?
Cu(I) - as it is a d10 metal ion
Cu(II) is a d9 metal ion and hence is less stable than d10
There are still many complexes of both however…
What is the trend of the energy required to ionise a metal to 2+ of the 1st series TMs?
There is a general increase from Sc to Zn
Though Fe is considerably lower since Fe(II) is d6 and hence stable
What’re generalisations about 4d/5d metals?
Higher oxidation states are more common and more stable than 3d metals
4d/5d metals are very similar to each other - due to Lanthanide contraction - but differ from 3d metal in group.
What are the main differences between Cr(VI) with Mo(VI) and W(VI)?
Cr(IV) is strongly oxidising whereas Mo(VI) and W(VI) are barely oxidising at all
(They form ionic lattices with MO3 and MO6 units)
[ReO4]- is quite inert - used as inert anion when cations are unstable
Whereas [MnO4]- is strongly oxidising
Compare high oxidation state oxides of Fe, Ru and Os
[FeO4]2- is Fe(VI)
But RuO4 and OsO4 are both M(VIII) - 4d/5d metal can accommodate higher oxidation state - d0 complexes
