4:3 Notes

What can appen when an atom absorbs energy?

An increase in kinetic energy or a phase change

Niels Bohr

Agreed with Rutherford's model but added something to it

Energy levels - the possible energies that electrons in an atom can have

When an atom gains energy an electron may move to a higher energy level

When it loses the energy, it emits it as light

No two elements have the same set of energy levels, so they emit different colors of light


Electron cloud model

Electron cloud model - model of the most likely locations for electrons in an atom (deals with probability)

Orbital - region of space where an elecron is likely to be found


Electron configuration

Electron configuration - arrangement of electrons in the orbital of an atom

Ground state - electrons are all in their lowest possible energy levels (most stable)

Excited state - one or more electrons are in a higher anergy level than usual (least stable)

Atoms emit light when their electrons return to ground state