Transition Metals Flashcards
With Mn / Ni / Zn?
pale brown / green / white.
What colour is the solid formed when NaOH is added to Fe 2 and 3?
green (brown on standing as oxidised) / brown.
Cu / Cr?
blue / green.
Which complexes dissolve in excess NaOH? Excess NH3?
Chromium and Zinc. Nickel, Copper and Zinc.
what colour can Cr3+ also be?
violet.
what is the coord number of copper’s complex with ammonia and which other ligand also?
4 - chloride ions.
Give the colours of vanadium in its various oxidation states.
VO 2+ - yellow.
VO2+ - blue.
V3+ - green.
V2+ - violet.
what is the eqm between chromate and dichromate ions - O.N.?
2CrO42- + 2H+ –> Cr2O72- + H2O
(yellow –> orange)
+6
what is the role of hydroxide ions in precipitation reactions?
remove H+ from water ligands.
Why are copper (1) compounds colourless?
d10 ion with full subshell so no d-transitions are possible.
what molecule is planar and linear?
[Pt(NH3)2Cl2] and [CuCl2]-.
amphoteric?
hydroxides which dissolve in excess OH- exhibit acid behaviour but also react with acids.
After the ligands cause the d orbitals to split in energy, what happens to the electrons?
Difference in energy corresponds to the wavelengths of light of some visible waves which are absorbed as electrons move from lower to higher energy levels.
which two d block elements are not transition?
Sc and Zn - 3+ and 2+ - empty + full.
why is it important to develop new catalysts?
lower energy use in industry
use waste from other processes
improved atom economy
reduced environmental pollution.
