9—14.
ELECTRON ENERGY LEVELS
211'
La, LB in the L series. This multiplicity of lines is accounted for
in the equation by slight changes in the value of a; Moseley’s law
is not exact, particularly for the lighter elements as may be seen
by the deviations from straight lines for smaller values of Z.
_—
The K series lines are of shortest wave-length as may be seen in
_
the diagram. Two other series, M and N are known but are so
soft as to require _a vacuum spectrograph for their study.
;
9-14.
Electron Energy Levels Near the Nucleus.—In chapter 7 we have seen that an atom contains a massive, positively
charged nucleus around which negative electrons are conned in a
number of known energy levels and that light is radiated whenever
the outer electrons move from exterior levels t0Ward inner levels
…
»
in the atom:
Figure 9—16 shows an energy diagram which may
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Fm. 9—16.
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