Atomic Absorption Sepctrum Flashcards
what gives gas filled lights their colors
an electric current passing through the gas in each glass tube makes the gas glow with its own characteristic colour
what is light
part of the electromagnetic spectrum
how does the energy of electromagnetic spectrum move
they are presented in waves of different frequencies and wavelengths
what frequency and wavelength does red have
longest wavelength
lowest frequency
what was bohrs discovery
electrons orbit in fixed energy shells around nucleus
electrons can exist at higher energy levels further from nucleus when they are excited
electrons furthe away from nucleus exist at higher energy levels
what happens when energy is absorbed by atom
electrons jump to an excited state
what happens if energy is removed from atoms
electrons move to original ground state
and a photon is emitted (no mass no charge)
what is an absorption spectruum
visible light spectrum with dark lines or gaps corresponding to wavelengths that are absorbed by the gas.
what is an emission spectrum
coloured lines on a black blackground that shows the electromagnetic radiation emitted due to electrons making a transition from high to low energy state
is energy needed to get electron to from ground to excited state and back the same
yes
what is the flame test
a platinum metal tip is dipped into a solution of the unknowns salt and then is placed in a bunsen burner and the heat excites the electrons in the vapourised metal ions of the salt
and when the electrons return to ground state, they emit a photon with the same frequency of wavelength that was absorbed t get electron from ground state to excited state.
what is spectroscopy
study of interaction between light and matter
what is AAS
Atomic Absorption Spectrum
analytical technique that relies on unique nature of an element’s absorption spectrum to identify its presence and concentration in a mixture
how does AAS work
certain elements can only absorb and emit certain wavelengths of photon cells, called the absorption spectra.
why is platinum rod used in flame test
unreactive
does not produce colour in the flame which will mask the colour of other ions
