a) Bohr's Atom Model (for Hydrogen: 1 proton + 1 electron)
1) several orbits with different radius for the electron of Hydrogen.
2) no photon absorbed: electron in smallest orbit (ground state)
3) a) photon with a specific wavelength absorbed: (visible light: 410,434,486,656 nm)
and electron is lifted into a larger orbit (excited state)
the higher the energy of the proton the larger the orbit: λ↑→ E↓ of photon
b) photon with same wavelength emitted (emission spectrum)
and electron falls back into its previous orbit.
b) Discoveries Niels Bohr incorporated into the Rutherford Model
1) Spectroscopy (measures the characteristic wavelength of light emitted by electrons of energized atoms)
wavelenght of emission spectrum of Hydrogen for visible light: 410,434,486,656 nm
Rydberg Formula: 1/λ=R*(1/n12–1/n22) [m-1] (includes also some invisible light)
R=1.097*107; n1=1,2,… ; n2= n1+1, n2= n1+2,…
2) wave-particle duality ( light particle=photon) Planck constant 6.626*10-34 Js
(a) each photon of light contains an energy quantum:
Planck relation E=hν=hc/λ [J] λ↑→ E↓ of photon
(b) 1 electron + 1 photon [quantum 1 plus quantum 2] Einstein's photoelectric effect
3) Rutherford Model: a) proton (+) in nucleus b) electron (-) in orbit
c) atom mostly empty d) #p=#e (neutral)
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