topic 6 Flashcards
explanation for why metals prefer certain ligands
hard + soft acids and bases
what is a lewis acid
accepts e- in order to form an adduct
METALS
what is a lewis base
donates e- in order to form an adduct
LIGANDS
describe a hard metal
a metal with a high positive charge
describe a hard ligands
small electronegative donor atoms o,n,f
bonding between hard metals and hard ligands
more electrostatic
more ionic bonding
soft metal
lower charge
larger size
more polarisable
soft ligand
large
polarisable donor atoms
bonding between soft metals and ligands
covalent character
trend across the first row of d block
from hard to soft metals
how does atomic number effect hydration energy
higher atomic number meanslower hydration energy
equation
Z^2/r
how does CFSE effect hydration energy of d block elements
it increases the hydration energy
metal ions that are smaller than their expected size have e- where???
e- in the t2g subset
these are weaker at repelling
making the ion smaller
what is a stability constant
constant thats value shows how stable smt is
the higher the stability constant B
the more stable the metal
M + nL -> <- intoo
MLn
B, stability constant is equal to ( equilibrium expression)
[MLn] / [M][L] ^n
how does CN effect a complex
increases the complex’ stability
irving williams series + stability constant following the sequence of IW when any ligand is used
Mn(||) <
Fe(||) <
CO(||). <
Ni(||). <
Cu(||) <
> Zn(||)
increasing stability
whats a chelate ligand
ligand with more than one donor site
binds to one metal with multiple donor sites at once
en
nh2-ch2-ch2-nh2
which ligands form more stable complex’
chelating ligands form more stable complexes than monodentate ligands
mono dentate ligands form complexes that
are not rlly stable
bi and multidentate ligands form complexes thatttt
are more stable then complexes with only monodentate ligands
chelate effect
driven by entropy
entropy increases
increase in entropy = wanted
ligand with 6 water + 3en turns into
ligand with 3 en + 6h2o
from 4 total things to 7 total things : increase in entropy bc increase in disorder
change in gibbs in standard condition issss
-RT ln( B)
B is the stability constant
what is B
stability constant
hard metals have a xxx ocidation state
higher
C N O F
soft metals have a xxx oxidation state
lower
As Se P S
