Coloured Ions Flashcards
What does colour of complex depend on
Coordination number, type of ligand bonded to ion, oxidation state of metal ion
What state are usually coloured
Aqueous solutions of transition metals
Which colours are seen
Those that have wavelengths that are transmitted, not those that have wavelengths that are absorbed by substance
How does energy of light change towards blue end of visible light spectrum
Increases
How would compound be red
Compound will absorb all frequencies of visible light spectrum apart from wavelength that causes red light which is transmitted to can be seen
What do reflected wavelengths correspond to
A specific colour characteristic to compound
Effect of ligands on d subshell of metal ion
Causes d subshell to split meaning some electrons exist in a slightly higher energy level (excited state)
What causes specific frequency of light to be produced
The change in energy between the states in split d subshell subshell, energy difference between levels affects how much energy absorbed when an electron promoted (d-d electron transitions) which governs the colour of light absorbed, transmitted frequencies seen which will be in visible light spectrum
Which ions are colourless
Those with full/empty d subshell as no available electrons to excite and do d-d electron transitions
What is the energy difference between split d subshells proportional to
The frequency of light absorbed
Why is zinc colourless
There are no empty or partially filled d orbitals into which an electron can be promoted as it has completely filled d orbitals
Why do different compounds have different colours
As energy gap between d orbitals is different in different metal ions so wavelength of light absorbed different when d to d electron transitions
