1. Distinguish between line spectra and continious spectra - continuous spectra occupies an interval of wavelengths but a line spectra is only for certain wavelengths
2. Emission spectra and absorption spectra - imposed on a continuous spectra, an emission spectra will be peaks and a line spectra troghs. Emission spectra are emitted by excited atomes decaying. Absorption spectra are due to electrons becoming excited.
3. Excitation and ionisation. Excitation - electrons move to a higher energy level. Ionisation - electrons are ejected from the atom/.
