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periodic oscillation that travels through space


distance between two corresponding points on a wave -


the number of waves passing a given point per second


vertical height of a wave from the midline. Proportional to energy.


distance per unit time (m/s)

speed of light

3.00 x 10^8 m/s


smallest packet of energy. Akin to the atom for mass.

threshold frequency

frequency below which electrons are not ejected in the photoelectric effect


quantum of light energy

emission spectrum

specific frequencies given off by excited atoms of individual elements

ground state

most stable arrangement for an atom

excited state

high-energy state


specific area in which an electron can exist


having the same energy

valence electrons

outermost bonding electrons

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