Electrons in Atoms and Light Spectrum Flashcards
Base of the energy line
Origin
All waves move at
3x10^8m/s
High point on a wave
Crest
Low point on a wave
Trough
Distance from origin to crest
Amplitude
Distance from crest to crest
Wavelength
The number of waves that pass a given point per second. Abbreviated by v
Frequency
Equation frequency and wavelength
C=yv
C=3x10^8 m/s
v=hz (frequency)
Y= m (wavelength)
Radio waves, microwaves, infrared
Left end of spectrum (red orange yellow) low energy
Low frequency, long wavelength
Ultra-violet, x-Rays,gamma rays,
right end of spectrum (blue indigo violet)
High energy
High frequency
Short wavelength
All colors combined
White light
Energy and frequency equation
E=hxv
h=plancks constant 6.6262x10^-34joulesxsec
v=frequency
Matter is made up of solid invisible particles
Democritus
One type of atom for every element
Dalton
Discovered electrons
Atoms were made of positive stuff
Negative electron floating around
“Plum Pudding” model
J.J Thompson’s model
Discovered dense positive piece at the center of atom- nucleus
Electrons would surround it
Mostly empty space
“Nuclear model”
Ernest Rutherford’s Model
Electrons move in circular orbits, amounts of energy separate on level from another
“Planetary model”
Bohr
Derived an equation that described the energy and position of the electrons in an atom
Schrodinger
It can tell us the probability of finding an electron a certain distance from the nucleus
Quanta is the amount of energy needed from one energy level to another
Orbits are not circular
The quantum mechanical model
The variable for the energy level of the electron
Principal quantum number (n)
Regions where there is a high probability of finding an election
Atomic orbitals
S orbital
# of shapes
Max electrons
Starts at energy level
# of shapes I max electrons Ienergy lev
1 I 2 I 1P orbital
# of shapes
Max electrons
Starts at energy level
#of shapes I max electrons I energy lev
3 I 6 I 2D orbital
# of shapes
Max electrons
Starts at energy level
#shape I max electrons I energy level
5 I 10 I 3F orbital
# of shapes
Max electrons
Starts at energy level
#shapes I max electrons I energy level
7 I 14 I 4Electrons enter the lowest energy first
This causes difficulties b/c of the overlap of orbitals of different energies
Aufbau principle
at most 2 electrons per orbital- different spins
Pauli Exclusion principle
When electrons occupy orbitals of equal energy they don’t pair up until they have to
Hund’s Rule
Speed of light
3x10^8 m/s
What type of wave is light?
Electromagnetic radiation
How are frequency and wavelength related?
Inversely related; as one goes up the other goes down
How are frequency and energy related?
Directly related; frequency x Plancks constant equals energy
Range of the variety of frequencies
Spectrum
Passing a white light through it separates it
Prism
Combination of all colors
White light
Absence of all colors
Black
Planck’s constant
6.6262x10^-34 joulesxsec
What is energy measured in?
Joules
Frequency measured in?
Hz
Wavelength measured in?
m
