Transition metals Flashcards
(35 cards)
ligand
a molecule or ion that forms a coordinate bond with a transition metal
complex
central metal atom or ion surrounded by ligands
coordinate number
number of coordinate bonds
transition metal
metal with a partially filled d sub shell
properties
variable oxidation state
form coloured ions
catalysts
complex formation
Chelate effect
bi or multidentate substitute monodentate to create a more stable complex
increase in disorder 🔺S more positive
mono +3bi -> bi + 6H2O 4mol to 7
🔺H = 0 is same number and same type of bonds broken and formed
reducing vanadium
Mn titrations colour
MnO4- is purple
Mn2+ is colourless
self-indicating
redox titrations ratios
with Fe 1:5
with C2O4 2- 2:5
energy gap equation
heterogenous catalysts
in a different phase to the reactants
Usually solid, reaction takes place on the surface
heterogeneous catalysts process
reactants adsorbed onto active sites, bonds are weakened as new bonds formed between reactants. Products are desorbed
Haber process and catalyst
Contact process
colorimetry use
used to measure absorbance of light, amount of light absorbed is proportional to the conc of complex ion
method for colorimetry
how to intensify colour in colorimetry?
add a suitable ligand
why is each vial the same size in colorimetry?
amount of light absorbed proportional to distance travelled through solution
what effects colour change?
oxidation state
coordination number
type of ligand
Explain why _ ions are [colour]
1d orbitals split in energy levels and d e- are promoted to higher energy d orbitals by absorbing energy in the form of visible light. The [colour] transmitted and observed is the light not absorbed.
why would a metal not show colour?
if it’s d10 (full shell)
e- can’t be promoted
no d energy levels can split
Cl- ligand
can only fit 4
Ag complex
always linear
Pt 2+
Ni 2+
square planar complexes
