Transcript Electrons in "Orbit"

Electrons “in Orbit”
Topic 2.1
• Emission line spectrum
– energy is applied to a specific element
• this “excites” the element and the light is viewed
through a spectroscope
– a continuous spectrum is NOT observed, but a series of
very bright lines of specific colors with black spaces inbetween instead
– unique for every element and are used to identify atoms
(much like fingerprints are used to identify people)
More on emission line spectrum
Give off energy
when falls back
down to
normal energy
level
– the process
• electrons surround the nucleus in specific orbitals
or energy levels
• when electrons are excited (heat/electricity) they
can move to a higher energy level
• when they move back down they emit energy in
the form of electromagnetic radiation
• because electrons can only exist in certain energy
levels, only certain transitions can occur
• the color of the light emitted depends on the
frequency of the emitted photon
• http://www.youtube.com/watch?v=QI50GBUJ48s
this is a repetitive slide- just couldn’t bear to delete it
1. an electron in the
atom gains (absorbs)
energy from heating
2. electron jumps up an
energy level.
3. electron is now
unstable (unwelcome)
in this level and is
“kicked out”
4. when the electron
loses the energy and
come back to the
original level, light is
emitted
The Atomic Emission Spectrum of
Hydrogen
• the emission spectrum of hydrogen is the simplest
emission spectrum because there is only one electron
– if had more than one electron, they would influence the
other’s position
– it is not uniform, but concentrated into bright lines,
indicating the existence of only certain allowed electron
energy levels
– Electron “jumping” website
– McGraw Hill animation link
convergence
up here
(levels are
close
together)