Atomic Spectra And Nuclear Radiation Flashcards
What is electromagnetic radiation?
Energy that’s transmitted as waves, with a spectrum of different frequencies
What happens to frequency along the electromagnetic spectrum?
Frequency increases, wavelength decreases
(Radio → gamma)
What does it mean when an atom is in its ground state?
All its electrons are at their lowest possible energy levels
What do absorption spectra look like?
Black lines on a bright background
What do emission spectra look like?
Bright coloured lines on a black background.
What does the emission spectrum measure?
The energy given out when electrons drop to lower energy levels
What does the absorption spectrum measure?
The electromagnetic radiation passing through the gaseous element, the electrons only abscub certain frequencies (which correspond to differences between the energy levels), soradiation passing through has certain frequencies missing.
How are the emission & absorption spectra related?
They are opposites of each other (the frequencies in an emission spectrum are the same as those missing in the absorption spectrum)
How do the lines on emission/absorption spectra change as the frequency increases?
The lines get closer together
What’s the equation that connects amount of energy (absorbed or emitted) to the frequency of the radiation?
Change E = hv
(Difference in energy between 2 shells (J) = Planck’s constant ( j/hz) x frequency (Hz))
What’s the equation that connects wavelength & speed of electromagnetic radiation?
C=v x wavelength
Speed of electromagnetic radiation (m/s) = frequency (Hz) x wavelength (m)
What is nuclear fusion?
When 2 small nuclei combine under high temperature & pressure to make one larger nucleus
Where does nuclear fusion naturally occur?
Inside stars
