Studied by 2 peopleWhat is a model that uses electrostatics to explain electronics in complexes?
crystal field
What is a model that uses molecular orbital approach in the structure of complexes?
ligand field
What do colors in transition metal complexes come from
energy HOMO-LUMO gap
What kind of coloration is glowing or light?
emissive coloration
What kind of coloration is paint or clothes?
absorptive coloration
We see the _____color of wavelengths absorbed
complementary
In an octahedral field, what d orbitals are not point at the axis
dxy, dyz, dxz
In an octahedral field, what d orbitals are affected most by electrostatic interaction?
dz2, and dx2-y2
octahedral d1 through d 3 have all _______ electrons
unpaired
octahedral d __ through d_____ have both high and low spin states
4-7
low spin means less _____ electrons
unpaired
If delta O is less than repulsion between paired electrons than electrons ______ want to pair
don’t
Ligands ____ the d-orbitals of transition metal complexes
split
Electrons fill into the orbitals based of the size of what
delta O
What influences the size of delta O
-size of metal
-charge of metal
-nature of ligand
big metals give a _____ delta O
larger
as the charge on the metal increases, delta O ____-
increases
Delta O increases as you go ___ to _____ across a period
left to right
What is the order of ligands from small delta O to large delta O
halogens< oxygen compounds< nitrogen compounds< carbon compounds
What d orbitals are higher energy for tetrahedral complexes
dxy, dyz, dxz
What d orbitals are lower in energy for tetrahedral complexes
dz2, dx2-y2
Delta T is always ____- than delta O
less
All tetrahedral complexes are ____ spin
high
What square planar d orbitals have the lowest energy
dxz and dyz
What square planar d orbital has the largest energy
dx2-y2
What ions are mostly square planar
d8 (Ni2+, Pd 2+, Pt2+, Au3+, Rh +, Ir+)
The delta SP is very ____-
large
square planar are typically
diamagnetic
What is beers law
absorbance= molar absorptivity x path length x molar concentration
Molar absorptivity indicates how __ a species undergoes a ______
efficiently; transition
a high molar absorptivity means
more photons absorped
What impacts molar absorpitvity
selection rules and geometry
The laporte rule is d-to-d transitions forbidden in ____ complexes
octahedral
Transitions that require the spin of an electrion to change are
forbidden
Tetrahedral complexes tend to be strongly
colored
most transition metals show ___ main electronic transitions
3
What is the equation for energy of transition?
energy= (hc/wavelength)
When more energy is enetering a system than leaving or vise versa it is called a
dynamic system
Enthalpy is hear flow measured at constant
pressure
state functions are
-size dependent
-additive
-value depends on the difference btwn 2 energentic states
what is it called when gas goes to liquid
condensation
what is it called when liquid goes to gas
vaporization
What is it called when a solid goes to a gas
sublimation
what is it called when a gas goes to a soild
deposition
what is a solid going to a liquid
melting
what is a liquid going to a solid
freezing
What process of phase changes are endothermic
melting, vaporization, and sublimation
What processes of phase changes are exothermic
freezing, condensation, and deposition
what does combustion produce
co2 (g) and H20 (l)
What is hess’s law
the summation of enthalpies
What are the standard conditions
25 C, 1 atm pressure, 1 M solutions
In enthalpy you assume that all elements have an enthalpy of _____ in their standard state
0
for enthalpy of balanced thermochemcial reactions you can use the equation
h rxn= hf products - hf reactants
What is the equation for estimating delta H using bond enthalpies?
Hrxn= h broken -h formed
In bond enthalpies phases of matter _____ taken into account
are not
What are the qualities common to spontaneous reactions?
-release heat
-form gases
-form precipiates
-form compounds with strong bonds
What is the most convient and precise way to measure delta H
using Hf values
What property of spontaneous reactions is hard to measure with enthlapy
forming gases
A _____ is one of any possible configurations in a system
microstate
What is the measure of the number of microstates available to the system being studied?
entropy
entropy ___- with pressure
increases
The _____ of particles increases the entropy of a system
mobility
When a scoop of ice cream melts entropy ____
increases
When a solid is turned into aqueous ions entropy ____
increases
When a liquid and gas turn into a solid and gas entropy____
decreases
What are the units of entropy
J/K
Delta S =
n(S products)- n (S reactants)
reactions that are spontaneous tend to be ___ and have an _______ in entropy
exothermic; increase
What is the equation for delta G
delta G= delta H- (temp(K) x delta S)
for a spontaneous process delta G has to be _____ zero
less than
-H and + S means the reaction is
spontaneous at all Temps
-H and -S means the reaction is
spontaneous at low temp
+H and +S means the reaction is
spontaneous at high temps
+H and -S means the reaction is
never spontaneous
The best way to calculate delta G is using
free energies of formation
When should you use delta G= delta H- (T x delta S)
when you need to determine TEMPERATURE of spontaneity and when entropy and enthalpy values are available
When should you use delta G- (products)- reactants
when only delta G values are avaible and you only need to determine spontaneity
What does Gibbs free energy have to be in order for a reaction to be spontaneous?
less than O (-)
What state functions do elements in their standard state = 0
enthalpy and Gibbs Free Energy
What are the units of delta G
kJ/mol
The equilibrium constant is ( ) over ( )
products; reactants
What drops out of the K expression
solids and liquids
the molarity of gas is what
mols gas/ Volume container
When reagents are added to a solution the equilibrium will shift
away from what was added
If an endothermic reaction is warmed where will the equilibrium shift
to the right towards the products
What are the top orbitals of an octahedral compound d orbital splitting diagram called?
eg
What are the bottom orbitals of an octahedral compound d orbital splitting diagram called?
t2g
What are the top orbitals of a tetrahedral compound d orbital splitting diagram called?
t2
What are the bottom orbitals of a tetrahedral compound d orbital splitting diagram called?
e
What is the order of square planar diagrams from bottom to top?
(dxz + dyz), dz^2, dxy, dx^2-y^2
What are the values of h and s for line A
h>0, s<0
What are the values of h and s for line B
h<0, s <0
What are the values of h and s for line C
h>0, s>0
What are the values of h and s for line D
under what conditions is the top line spontaneous
never spontaneous
under what conditions is the 2 line spontaneous
spontaneous at low temps
under what conditions is the 3rd line spontaneous
spontaneous at high temps
under what conditions is the bottom line spontaneous
always spontaneous
Note
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