• The chromophore is the part of a molecule that produces its colour.
  • Things appear to have colour because they absorb certain wavelengths of light while reflect others.
  • When wavelengths of light within the visible spectrum enter the human eye, the observer perceives this as colour.
  • The chromophore is the part of a molecule where there is an energy difference between two different molecular orbitals.
  • A molecular orbital refers to the position and wave-like behaviour of an electron as it moves around an atom’s nucleus.
  • If the energy difference of a chromophore falls within the range of the visible spectrum (2 to 2.75 electron volts) then it will produce colour.
  • The colour produced by a surface or object corresponds with wavelengths of light that are not absorbed during their interaction with the chromophore.