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

Thomas Young double slit experiment video

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