9

According to Wikipedia,

[...] It is a colorless solid that readily sublimes into intensely yellow vapors.

It is clear from the above statement that $\ce{XeF6}$ is colourless in solid form. But why should it be coloured when it converts into vapour form?

Buck Thorn
  • 21,621
  • 5
  • 38
  • 89
Infinite
  • 1,634
  • 1
  • 5
  • 25
  • https://chemistry.stackexchange.com/questions/82350/what-is-the-molecular-structure-of-xenon-hexafluoride https://chemistry.stackexchange.com/questions/50187/what-is-hybridisation-of-xef6-in-solid-state – Mithoron Sep 09 '22 at 18:19
  • Bottom line is it depolymerises. – Mithoron Sep 09 '22 at 18:27
  • There is nothing unusual about vapors of elements/compounds appearing colored. It is a common phenomenon. Potassium is a silvery white metal but its vapors appear green! Sodium also shows colored vapor. People have spent their trying to understand the structure of xenon hexafluoride. – AChem Sep 09 '22 at 23:49
  • Related for oxygen: https://chemistry.stackexchange.com/questions/15035/does-o2-have-a-color-in-the-gas-phase Oxygen is colorless at gaseous state but is slightly colored in liquid and solid state. – Nilay Ghosh Sep 10 '22 at 04:08
  • 1
    @NilayGhosh, This oxygen issue is perhaps a different phenomenon. It is simply a concentration effect (Beer's law). Just like heavy water appear blue when viewed in a very long path length tube but in an ordinary beaker it is colorless pure white liquid. Xenon hexafluoride is complicated in the sense that there must be a change in the nature of bonding in the solid phase and gas phase. Just like potassium and sodium vapor. One would never assume that potassium has a beautiful green vapor. – AChem Sep 10 '22 at 15:59
  • H2O is definitely blue in large quantities by transmitted light. D2O is colorless because the stretching frequency overtones do not reach into the visible. – jimchmst Mar 17 '24 at 17:00
  • O2 gas is definitely colorless. How long a path is necessary to see that? There are condensed species in the liquid and various solid phases. – jimchmst Mar 17 '24 at 17:15

0 Answers0