- #1
H Psi equal E Psi
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Thread moved from the technical forums, so no Homework Template is shown
Hi Everyone
I'm studying material Engineering and I'm currently preparing chemistry for the summer exams.
Now, there is an old exam question which I don't know how to solve:
"In which temperature range does ##[W^{+VI}F_{6}^{-I}]## melt?"
My solution:
Well, the 18-Electron rule is not fulfilled. There is no crystal field stabilization energy since there are no d-electrons and there are no Pi-backbonds. But:
The electronegativity difference is larger then 1.5. Wolfram is a hard acid and Fluor a hard base. The lattice-energy is very high because both compounds are in a high oxidation state and have a small atom radius (especially Fluor).
Based on this i would say ##[W^{+VI}F_{6}^{-I}]## has a melting-point over 1000 degrees Celsius.
I then looked it up on Wikipedia and it says that ##[W^{+VI}F_{6}^{-I}]## is a gas!?
How can one know this?
And is my train of thought correct? Because our professor ask this kind of question every time... He asked it once with ##OsO_{4}##, ##GeCl_{4}##,...
Thanks a lot for your help!
I'm studying material Engineering and I'm currently preparing chemistry for the summer exams.
Now, there is an old exam question which I don't know how to solve:
"In which temperature range does ##[W^{+VI}F_{6}^{-I}]## melt?"
My solution:
Well, the 18-Electron rule is not fulfilled. There is no crystal field stabilization energy since there are no d-electrons and there are no Pi-backbonds. But:
The electronegativity difference is larger then 1.5. Wolfram is a hard acid and Fluor a hard base. The lattice-energy is very high because both compounds are in a high oxidation state and have a small atom radius (especially Fluor).
Based on this i would say ##[W^{+VI}F_{6}^{-I}]## has a melting-point over 1000 degrees Celsius.
I then looked it up on Wikipedia and it says that ##[W^{+VI}F_{6}^{-I}]## is a gas!?
How can one know this?
And is my train of thought correct? Because our professor ask this kind of question every time... He asked it once with ##OsO_{4}##, ##GeCl_{4}##,...
Thanks a lot for your help!