GenChem1 - 1B quantum theory

what is so special about the quantum theory?

the fact that energy can only transfer in certain amounts

how was electromagnetic radiation further investigated?

with heat

what happens when you increase the temperature of a metal?

it begins to glow red (incandescent) and with even more heat, it becomes a black body and glows white.

what is the relationship between temperature and wavelengths?

as temperature increases, wavelength decreases

what did wilhelm wien do?

discovered shift in color of black body as temperature increased; wien’s law Tλ=2.9mm(K)

what did max planck do?

proposed exchange of energy between matter and radiation occurs in quanta; E=hν

what was the ultraviolet catastrophe?

the incorrect prediction that objects emit infinite amounts of energy from a regular amount of thermal glow every object has.

what is intensity?

the # of photons being emitted

what does E=hν represent?

energy of 1 photon

what is the photoelectric effect?

the idea that each metal has its own threshold E and if the radiation surpasses that threshold, electrons are emitted, even at low intensity, and KE increases with ν

if hν > Φ, what does that mean for the electron?

electron is emitted with KE = mv²/2 = hν - Φ

what is the wave-particle duality?

particles are particles, but they also behave as waves. so, λ = h/mv and mv=p

what is the uncertainty principle?

the idea that the position and momentum of at wave cannot be known at the same time; so, △p(△x) ≥ 1/2ℏ where ℏ = h/2π