If Trioxide refers to Ozonide ion, the formula is O3-
N2o3
You don't say that. What you do say is that the valency of sulphur in sulphur trioxide is 6.
2 sulfur 3 oxygen S2O3
trisulfur septoxide
A sulfone contain the structure S(=O)2-R' where R' is an organic group.
The chemical formula for dinitrogen trioxide is N2O3.
SO3 is the chemical formula for sulfur trioxide.
Formula: SO3
The chemical formula for Disilicon trioxide is Si2O3.
The formula for xenon trioxide is XeO3.
Formula: XeO3
Formula: SO3
The chemical formula for tellurium trioxide is TeO3.
Formula: B2O3
Arsenic trioxide refers to Diarsenic trioxide = As2O3 . It is not to be confused as AsO3 which does not exists.
The correct formula for nitrogen trioxide is NO3.
The chemical formula for diphosphorus trioxide is P2O3.