Unit 3: continued Flashcards
what are the three principals for filling orbital notation with electron configuration?
- aufbau principle, hund’s rule, and pauli exclusion principle
aufbau principle
states that electrons enter orbitals of lowest energy first (1s before 2s)
hund’s rule
states that when electrons occupy orbitals of equal energy, one electron enters each orbital until all the orbitals contain one electron with parallel spin.
pauli exclusion principle
states that no two electrons in the same atom can have identical values for all four quantum numbers
quanta
a specific, discrete amount of energy required to move an electron from one energy level to the next.
equation Quanta = h * v where v=frequency and h=planck’s constant (they are like packets of energy.)
the electron quickly returns to a lower shell, emitting the _______ amount of energy, a ______
same, photon
what forms of light energy can be given off by an electron?
infrared, ultraviolet, or visible light
spectroscope
an instrument used to separate lines of light which appear as one color to the eye
explaining spectral lines
- experiments in the early 1900s involved light and matter.
- Plank and Einstein both provided info on the dual wave-particle nature of light.
planck’s contribution
some particles have wavelength properties
einstein’s contribution
some wavelengths have particle properties.
electromagnetic radiation
radiant energy that exhibits wavelength-like behavior and travels through space at the speed of light in a vacuum
what is the symbol for waves?
lambda, looks sort of like mandarin for “person”
what are the three primary characteristics for waves?
wavelength, frequency, and speed
wavelength
distance between two crests in a wave
frequency (of a wave)
the number of waves that pass a given point in space per second (unit s superscript -1)
what is the speed of light
3.0 x 10^8 m/s
c =
speed of light
amplitude
distance between peak/trough and midline
what are the names for the topmost and bottom most points on a wave
peak and trough
wavelength and frequency have a ______ relationship
inverse
unit for wavelength
meters (YOU HAVE TO CONVERT FROM NANOMETERS)
how to convert between frequency and wavelength
frequency = c / wavelength
light quanta are called
photons
in 1905 Einstein proposed that light could be describe as
quanta of energy that behaves as particles
E = mc^2
energy and frequency formula
Energy of a photon = frequency * planck’s constant
what is planck’s constant
6.6262 x 10^-34 joules, h is symbol
what is the change in energy formula?
delta E = h*v
what is the change in energy formula in terms of wavelength?
change in energy = h*c/wavelength
what is the rydberg constant?
1.097 x 10^5 per cm
formula for the energy of hydrogen electron?
E sub n = -R/n^2
change in energy formula for PEL transitions
change in energy = final energy - initial energy
continuous spectrum
when all the colors transition into each other, containing all the wavelengths of light
Emission Line Spectrum
a line spectrum when viewed with a spectroscope, it contains only some of the wavelengths of light
each atom has it’s own distinct pattern of emission lines representing different wavelengths of energy being released by the electron as it moves from excited to ground state.
paschen series
transitioning to PEL 3
balmer series
transitioning to PEL 2
lyman series
transitioning to PEL 1
absorption spectrum
- opposite of the emission spectrum
- represents the energy transition as the e- goes from the ground state to the excited state
- produces bands of darkness where energy is being absorbed
concerns of Bohr’s model
- this model did not explain why an electron stayed outside in orbits instead of falling into the positive nucleus
- could not explain the spectral lines of any other element besides hydrogen
what is the kernel of the lewis electron dot structure?
the nucleus + core electrons, represented by the elements symbol
there will never be more than ___ electrons in the valence shell
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