Unit 2 - Quantum Theory Flashcards
What equation describes the relationship between wavelength and frequency?
λ = c/v
c = speed of light
v = frequency
What is the relationship between frequency and energy?
E = hv
h = planck’s constant
v = frequency
What is the relationship between wavelength and energy?
E = hc / λ
h = planck’s constant
c = speed of light
What is the formula for kinetic energy?
KE = Enegry of photon - Work
What is the formula for thershold wavelength?
thershold λ = hc / W
h = plank’s constant
c = speed of light
w = work
What are the values of quantum number l?
- s = 0
- p = 1
- d = 2
- f = 3
How can you calculate number of angular nodes?
number of angular nodes = l
How can you calculate number of radial nodes?
number of radial nodes = n - l - 1
What plane is the angular node of 2px located?
xz plane
What plane is the angular node of 2py located?
xz plane
What plane is the angular node of 2pz located?
xy plane
What does a superscript on the axis subscript indicate?
ex: 3dz^2
It indicates that the electron density is along the specified axis.
What does a superscript on the axis subscript indicate?
ex: 3dz^2
It indicates that the electron density is along the specified axis.
What are the features of radial factors?
R(r) x r
- represents wave function
- number of times graph crosses x-axis = number of radial nodes
- when l = 0 (s), there is a maximum at r = 0
- when l = 1-3 (p,d,f), there is a zero at r = 0
What are the features of radial electron densities?
R(r)^2 x r
- represents probablility of electron density
- maxima decreases as r increases
- when l = 0 (s), maximum at r = 0
- when l = 1,2,3 (p,d,f), zero at r=0
What are the features of radial distribution plots?
r^2 R^2 x r
- represents average distance between nucleus and electrons
- maxima increases as r increases
- number of maximum = n - l
- all plots start at 0,0
- maximum = most probable distance, increases as n increases, decreases as l increases
What is the relationsip between wavelength and mass?
Inverse: larger mass, shorter wavelength; smaller mass, longer wavelength
How do you convert between nm and m?
- m to nm: multiply by 10^9
- nm to m: multiply by 10^-9
How do you convert beteween J and kJ?
- kJ to J: multiply by 10^3
- J to kJ: multiple by 10^-3
What was de Broglie’s hypothesis?
- electrons can have wave-particle duality
- de Broglie wavelength = h/mv
If an electron moves from n=4 to n=2 is energy emitted or absorbed?
emitted, positive E
If an electron moves from n=2 to n=4 is energy emitted or absorbed/
absorbed, negative E
What is the relationship between energy and wavelength?
Inverse
