Post on 14-Jan-2016
waves
speed of light(c) = 3.0 x 108 m/s or 186,000 miles/s
c= νλ
λ = wavelengthν = frequency
ν inversely related to λ
The Ionosphere and Radio Wave Propagation the D layer is good at absorbing AM radio waves D layer dissapears at night.... the E and F layers bounce
the waves back to the earth this explains why radio stations adjust their power output
at sunset and sunrise
Niels Bohr
• only works for hydrogen• no other spectral lines match the energy
of the electrons• doesn’t explain why electrons don’t fall
in to nucleus• electrons give off energy and move toward
nucleus, yet they never fall in to the nucleus• if e- fell in to the nucleus, matter would not
exist
quantum mechanic video
Max Planck(1858-1947)• founder of quantum theory• studied electromagnetic radiation
emitted from objects• determined the radiation was given off in
specific amounts• quanta
• separated physics • classical physics - study of particles, forces• quantum physics – study of wave/energy
and particle interaction
video
Albert Einstein(1879-1955)• evaluated photoelectric effect
• Showed that electrons could be ejected from a metal surface by shining a specific frequency of light on that surface
• mathematically proved the frequency of light contained quanta of energy• referred to these as particles of energy
• photons – particles/bundles of energy• light(energy) is a wave(classical)• light(energy) is a particle? (quantum)
Erwin Schroedinger(1887-1961)• mathematically derived an equation
that proved an electron has wave-like properties• electron is a particle (classical physics)
• behaves as particles should• affected by forces• has mass
• electron is a wave (quantum physics)• has wave properties
• double slit experiment• wavelength and frequency can be measured
Louis de Broglie (1892-1987)
• derived an equation that could explain the wavelength characteristics of all matter• λ = h/mv
• λ = wavelength• h = Planck’s constant (6.626 x 10-34 jxs)• m = mass of particle• v = velocity of particle
• the wavelength of an electron matches the distance electrons are found from the nucleus
Wave-Particle Duality theoryDouble Slit Experiment with Light
The observer in double slit experiment (youtube video)
Wave-Particle Duality theory
Wave-Particle Duality theory
• waves exhibit particle-like properties• photons• photoelectric effect
• particles exhibit wave-like properties• frequency and wavelength of particles• dual slit experiment
• waves and particles are interchangeable
video
Quantum Mechanical Model• Schroedingers Cat-Thought Experiment
Heisenberg Uncertainty Principle• the exact position and momentum/speed of
a particle cannot be simultaneously known• large particles have little uncertainty
• baseball• due to the baseballs large mass the amount of
uncertainty of where the ball is or how fast the ball is traveling is very small(not measurable)
• small particles have high uncertainty• electron
• due to the electrons small mass the amount of uncertainty of where the electron is or how fast the electron is traveling is very large(can’t know position if momentum is known, can’t know momentum if position is known)
video
Quantum Mechanical Model• visual example• bees around a hive
• bees are electrons
• currently accepted model of atom• most probable location of electrons
described with quantum numbers• can’t know exact position or path
• predict most probable location of locating an electron in a specific region around the nucleus• similar to predicting Mr. Andresen’s location in
the school at any given moment
video
Quantum Numbers• quantum numbers describe most probable
location of electrons around the nucleus(3-D model)
1.Principal Quantum number• denotes distance electrons are from
the nucleus• similar to the number of floors in a
building• NRG levels
• whole numbers 1 - ∞(7)• 1st nrg level is closest to nucleus• 7th nrg level is farthest from nucleus
Quantum Numbers2.Orbital(angular momentum)
Quantum number• indicates the shape of where the
electron is most probably located within the NRG level• similar to the shape of a room in a
building• denoted by letters s, p, d, f, (g, h, i, j…)
• s-orbital smallest• lowest NRG orbital
• f-orbitals largest, most complex• highest NRG orbital
Quantum Numbers• s-sublevel
• 1 - spherical shaped orbital• only 1 orbital/NRG level
• p-sublevel• 3 - peanut shaped orbitals
• start on 2nd NRG level
• d-sublevel• 4 - four leaf clover shaped + unique shape
• 5 orbitals/NRG level(starting with 3rd NRG level)
• f-sublevel• 7 very complex shapes(flower petals)
• 7 orbitals/NRG level(starting with 4th NRG level)
Quantum Numbers3.Magnetic quantum number
• indicates the position of each orbital in the nrg level with regard to the three axis(x, y, z) in space• s-orbital only has one position
• sxyz – sphere is positioned on all three axis equally
• p-orbital has three positions• px, py, pz = p sublevel
• d-orbital has five positions• dxy, dxz, dyz, dx2-y2, dz2 = d sublevel• too complex for us
• f-orbital has seven positions• 7 orbitals = f sublevel• way too complex for us
Quantum Numbers4.Spin Quantum number
• indicates the spin/magnetic field orientation of the electron• according to classical physics, a charged object that is
spinning creates a magnetic field• electrons have a magnetic field, i.e. they are
“spinning”• denoted with +1/2 and -1/2• also denoted with , • each orbital position can hold a maximum
of 2 electrons but they must have opposite spin(Pauli’s Exclusion Principle)• s-sublevel(1 orbital) = 2 electrons• p-sublevel(3 orbitals) = 6 electrons• d-sublevel(5 orbitals) = 10 electrons• f-sublevel(7 orbitals) = 14 electrons
NASA and Google team up to create a quantum computer(click here)
diagramming e- in an atom
orbital notation e- configuration e- dot diagram