Atoms and Nuclei

Nucleus radius: 1x10-15 Atom radius: 1x10-10 If the nucleus was the same size as the sun, how far would the electrons be from it?

Spectra (Hydrogen) 1/λ = R(1/N2 – 1/n2) R = 1.097x107 m-1 What are the min. and maximum values for the wavelengths emitted when hydrogen falls to the N=2 state (Balmer Series)

Bohr Model rn = (5.29x10-11) n2/Z (m) En = (-2.18x10-18) Z2/n2 (J) En = (-13.6) Z2/n2 (eV) Z = Atomic # n = orbital #

Bohr Model F = kq1q/r2 and ac = v2/r. Since F = ma, we have kQq/r2 = mv2/r. Thus mv2 = kQq/r. This means that 2KE = -EPE

Quantum Physics

Nuclear Structure A = Z + N A = nucleon # or atomic mass number Z = number of protons N = number of neutrons r = (1.2 x 10-15)* A1/3 m The density of nuclei are approx. the same.

Nuclear Fission/Fusion E = mc2

Radioactivity U Th + H Th Pa + e P P + γ