Quantum MechanicsThe Atom, Light, and Quantum Mechanics

http://www.ted.com/talks/angela_lee_duckworth_the_key_to_success_grit

The Quantum Mechanical Model

Electron Cloud Model: Now called The Quantum Mechanical Model

The Quantum Mechanical Model

Developed by Erwin Schrodinger in 1926

What is it?

It addresses…

1. The dual nature of matter and energy

2. The study of the wave nature of really, really tiny objects

3. The allowed amounts of energy to change the electrons energy level

The Quantum Mechanical Model

Quantum: a quantum of energy is the amount of energy required to move an electron from one energy level to another energy level.

Each electron is quantized. Has a SPECIFIC energy requirement.

The Quantum Mechanical Model How likely is it to find

an electron around the nucleus?

Described by probability… Calculated using VERY advanced and complicated mathematical expressions.

Think about the marbles

The Quantum Mechanical Model This probability is represented using

the Atomic Orbitals.

It is the region of space that has a high probability of finding an electron.

Has energy levels associated with it called

Principal Quantum Number (n=1,2,3,4,…)

The Quantum Mechanical Model

Each energy level has a shape associated with it…

S1 orbital2 electrons max

P3 orbital6 electrons max

D5 orbitals10 electrons max

The Quantum Mechanical Model

f7 orbitals14 electrons max

YOU are responsible for orbital shapes for s and p.

The Quantum Mechanical Model

LIGHT: The Electromagnetic Spectrum

The Quantum Mechanical Model

Electromagnetic Radiation

The Quantum Mechanical Model

Amplitude, wavelength, frequency, hertz

Units of frequency:Hertz (Hz) = s-1 = 1/s= #cycles per second

The Quantum Mechanical Model

Frequency and Wavelength are inversely proportional.

Lambda (m), nu (s-1), c (m/s)

The Quantum Mechanical Model

Atomic Spectra Pass an electric current through a

gas (atoms), it energizes the electrons.

The electrons move into higher energy levels. When they lose the energy and return to the lower energy level, they emit light.

The Quantum Mechanical Model

Atomic emission spectrum of an element is like the fingerprint of the element.

It shows the frequencies of light that is emitted by the element

Each element is unique!

The Quantum Mechanical Model

Mercury: Blue Nitrogen Gas: yellowish-orange

Lithium Ion: Red

The Quantum Mechanical Model

Light (photons) is energy. Particles are matter.

Both can behave as waves (energy) or matter.

This is called the wave-particle duality.

Proven by the famous double-slit experiment

Photons and Electrons had the same patterns of distribution!

Quantum VS Classical Mechanics

Classical mechanics describes the motions of bodies much larger than atoms (like us!).

Quantum mechanics describe the motions of subatomic particles and atoms as waves.

The Quantum Mechanical Model

Heisenberg Uncertainty Principle

States that it is impossible to know exactly both the velocity and the position of the electron at the same time.

The more sure you are about how fast it is moving, the less sure you are where it is…

http://www.pbs.org/wgbh/nova/physics/heisenberg-humor.html

Schrodinger’s Cat

http://www.newscientist.com/blogs/nstv/2011/09/one-minute-physics-is-schrodingers-cat-dead-or-alive.html

Quantum Mechanics Are Weird…

Physicist John Wheeler has said, “if you're not completely confused by quantum mechanics, you don't understand it.” Richard Feynman said “it's safe to say that nobody understands quantum mechanics. It works great, but if they tell you why they know how it works, they're lying to you.”• Wave-Particle Duality

• Electrons changing patterns when being observed• Time Dilation (Twin Paradox)• Time travel and Worm Holes?!• Tunneling• Bring in 2 places at once• This is where all the science fiction is created… Quantum

Physics

• Watch: The Inexplicable Universe: Spooky Universe (Netflix)