Pchem test 3.txt
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 Lambda
 Wavelength


Frequency and wavelength relation
Lambda v = c

Frequency unit
Hertz s(1)

Period
Reciprocal of frequency (time between peaks)


Why use sin with spring constant?
Twice differentiated is equal to sin

Where is natural frequency iused
Simple harmonic motion

Node
Intersection of wave with 0


Period
Time between peaks, inverse frequency

When is sin =0
For any integer*pi and for 0

Where is energy maximized?
Antinodes

What is h
Plancks constant. Ties wavelength to energy per packet.

Work function
Hv= kinetic energy of electron+work to remove electron

Threshhold frequency
Minimum frequency (w/h) to remove electron from surface

Stationary mode
Energy level at which electron emit no energy

How is hv tied to changes in energy state?
hv=E2E1

Ionization energy
Energy needed to move an electron to infinity

Rydberg constant
Value used in deriving wavelength average from mjultiple spectral lines?

Crystals are distinguished from amorphous solids by
Representative unit of molecular structure repeated at fixed intervals.

Basis
Structural init of a crystal

Lattice
Unifor arangement of points in space repeatyed in cristal styructure.

Crystal lattice
3d lattice

Space lattice
2 d lattice

Primitive cell
Minimum volume of the 3d crystal

Molecular bonding
Held together by temporary van der waal forces

Ionic bonding
Held together by interaction of shared ions

Covalent boonding
Atoms with similair charges share electrons to comlete orbital

Hydrogen bonding
Partial charges bresponsible for bonds of this type.

Intermediate type bonding.
A large anions field of electrons is disturbed by a nearby ion

Metal bonding.
Sea of electron

Lattice energy (inc E_c)
The energy of a crystal lattice

Speed of light
Wavelength*freqiency

Energy
Planck*frequency=plank*speedoflight/wavelength

Momentum operator
H/i d/dx= ihd/dx

Hamiltonian operator
Energy*psi=Hamiltonian*psi

How do we determine if gtwo functions orthoganol?
Integral of a*b dtau =0

Energy of sublimation
Energu to go from solid to gas

Order of lattice strength
Van der waal hydrogenmetaliccovalent ionic

London vanderwaal bond energy
Sum of forces modelled by leonard jones method. Based on partial charges as function of (1?r)^12 (1/r) ^6

Bond energy of metal
Enthalpy of sublimation to mono atomic gas. Found as function of vapor pressure

Intermolecular
Between molecules

Ntramolecular
Inside the molecule

Melting point increases with
Bond strength

Bond energy of hbond or dipole dipole
Based on partial charges as function of (1/r) ^6

Bond energy of cobvalent solids
Enthalpy to convert into gas phase, can be calculated with density functional theory

Ionic solid crystal lattice energy
Calculated using hesss law

Hesss law steps (5)
 1) calculate metals heat of sublimation
 2) calculate metal gas ionization energy per chatge
 3) if gas is diatomic, calculate dissociation energy
 4) calculatge gass electron affi nity for charge number
 5) sum and subtract solids enthalpy of formation

Ionic crystal internal bond energy
(Chargeanion)(charge cation)/r

Physiadsorption
Adsorption onto a surface caused by van der waals forces. Typically week and unimporgtant. Can however occur quickly and spontaneously

Chemiadsorption
Covalent adsorption onto a surface modelled by langmuir. Slow and rarely spontaneous due to high activation energy

When does surface become saturated in langmuir model?
High vapor pressure leads to 100% unilayer coverage

What is sign of enthalphy h of adsorption


What is sign of entropy s of adsorption


What is sign of gibbs for adsorption


Difference between graph of langmuir vs bet coverage.
 Langmuir reaches a flat surface at 100% coverage by monolayer.
 BET can have multiple layers so aftwr initial asymptote starts rising again

Langmuir hinschelwood.
Bimolecular reaction catalyzed by surfacwe. At some level (stoich ratio) rate peaks and then tapers off if conc of one increases while other stay constant

Langmuir hinschelwood if one or both sunstance sorb weak
Then that substance will drop out of bottom of eqjatipon

Langmuir rideal
Competitive adsorption, but b need bond surface and a must be gas for reaction

Linier momentum operator
ih_hat(d/dx)

Kinetic energy operator
(h_hat^2/2m) DEL^2

Hamiltonian operator
ihat^2/2m del^2 + E_HAT_P

Blackbody average energy
E_bar = k_b T

Stationary state.
State n in which electron emitsz no radiatoin

Change in energy between state 1 and 2
Planck*frequency = E2E1

Ionization energy
Energy needed to remove elecytron

Rhydberg formula
Shows average frequency (1/wavelength) of an emission spectra

Energy to momentum relations
 Momentum * speed of light
 Momentim*wavelength*frequency

Wavelength to plank relations (2)
 Wavelength=planck/momentum
 =planck/massvel

Heisenburg 3 forms
 Inc location* inc momentum >= H_BAR/2
 incE Inc t >=h_bar/2
 Incq incu=hbar/2m