Spectra PPT Flashcards
how are electrons arranged in atoms
in shells, valence shells
do outer electrons shells (that are outisde the electrons shelles with electrons have electrons)
no as they do not have any electrons to carry
can electrons exist between the shells
no
can electrons be promoted from ground state (base valence shell) to an excited state (a valence shell above base shell)
yes if they are excited
what happens when electrons return to their ground state from excited states
they release their energy as photons (light cells)
how do we excite electrons
use a spark
use heat
use light
how is light used to excite electrons
light passed through the gas will have some colours missing as some of the light will be used to exicte the electron which is why some colours are not seen
how are the energy difference levels determined
they are determined by measuring the freqeuny of the emitted photon
this was how scientists verified the existence of energy shell within atoms.
how are line emission spectra produced
when individual atoms that have been excited by heat, electricity or other light photons return to their ground states
what are line emission spectras
consists of bright lines on a black background
what line are produced in the emission spectra
they produce lines in the Infrared and Ultraviolet sections of the spectrum as well as the visible
what are the uses and application of emission spectra
determining the mineral contents of ore
determining composition of stars
producing light
natural light shows
