Chapter 7 Cheat Sheet

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waves- A vibrating disturbance by which energy is transmitted

wavelength (λ)- distance b/n two points

frequency (ν)- # of waves that pass through a pt

amplitutde- vertical distance of a wave

measured in Hz

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Formulas

Speed of waves

u=λν

energy of a single quantum

E=hv

E=hc/λ

Energy of a photon

E=hv

Electrons aquiring kinetic energy

hv= KE+W

Energies e- can obtain in H

En=-RH (1/n2)

Rh constant= 2.18x10-18 J

Change in Energy state

triE=Ef-Ei

De Broglie dual nature

λ=h/mu

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Electromagnetic waves-A wave that has an electric field component and a mutually perpendicular magnetic field component

same, wavelength, frequency, and speed

the energy given off is electromagnetic radiation

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emission spectra- Continuous or line spectra emitted by substances

every element has unique emission spectra

line spectra- light emissions at specific wavelengths

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Planck's Quantum Theory

Quantum- smallest amount of E that can b emitted or absorbed

Always emitted in intervals; hv, 2hv, 3hv

Planck's constant: 6.6310-34 J * s

Photoeletric Effect- Einstein

A phenomenon in which electrons are ejected from the surface of certain metals exposed to light of at least a certain minimum frequency

Photons- particles of light

Electrons r held in metal by attractive forces

if frequency of photons matches E holding e- they will come loose

if higher they will become loose and get some kinetic energy

more energy of photon more KE

Light behaves like particles and waves (particle wave duality)

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Bohr's Theory of H atom

energies of electrons r quantized, why they don't spiral out of control

Emitting energy- e- drops from higher energy to lower

Absorbing energy- e- goes from lower to higher energy

Ground state-lowest energy state of system

Excited state- higher energy state than ground state

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Dual Nature of Electrons

De Broglie asked if e-s can behave like particles, maybe e- can behave like waves

Quantum Mechanics

Heisenberg uncertainty principle- can't know the position and momentum of a particle at the same time

Shrodinger Equation- wave function

wave function squared is probality used to find where electron located

Electron density- where an e- might be located

atomic orbial- wave function of an e- in an atom

Rlly only works 4 H becuz it has 1 e-

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