He

1
ENERGY OF ELECTRONS ENERGY CONSERVATION
1. IONIZATION ENERGIES
EI1 2375
EI2 5248
2
Repulsion
1s1
He2
He
He
Energy kJ/mol
0
E i1 2375
-2375
E i2 5248
E He electron
electron lower energy (more negative) since has
more attraction to nucleus
E destabilization from e repulsion
-5248
E Heelectron
E i1 E destabilization E i2
ENERGY CONSERVATION
photon
2. PHOTOELECTRIC EFFECT
E kin
y mx b
E in E out hn E ion E kin
OR
n
E kin hn b OR E kin b hn OR E kin E
ion hn
b
ENERGY CONSERVATION
ENERGY CONSERVATION
photon
energy in
1
Heat, electrical
E
3. H EMISSION SPECTRA
2s
0
n 2
-328
E -1312/n2
DE electron E1 E2 -1310 (-328) - 982
(DE electron E final E initial E1 E2)
n 1
-1310 kJ/mol
ENERGY CONSERVATION DE electron E photon 0
or - DE electron E photon hn 982 kJ/mol