Home > Community > Is SO3 more electronegative than SO2?
Upvote

19

Downvote
+ Inorganic chemistry
+ Electronegativity
+ Chemistry
Posted by
Keith Roman

Is SO3 more electronegative than SO2?

Anthony Nelson  Follow

If by this question you are asking what is the oxidation state of sulphur in SO3, the answer is 6+.

You can work it out like this: we know that the oxidation state of O is 2- (this is what it always is), and because there is no charge on the compound, we know that the oxidation states cancel out to make 0. Therefore 0=(3x-2)+S, which can be rearranged to S=-(3x-2), therefore S=6.

More

Upvote

VOTE

Downvote
Barbara Davis  Follow

The concept of electronegativity is only applicable and relevant to the chemical elements in the periodic table. It is not relevant to chemical compounds, irrespective of whether the compounds are ionic or molecular.

In SO3, sulfur trioxide, the oxidation number of sulfur is +6 whereas it is +4 in SO2, sulfur dioxide. This makes SO3 a more powerful oxidising agent than SO2. And, SO3, the anhydride of sulfuric acid, is much more acidic than SO2, which is the anhydride of sulfurous acid.

SO3 also has very high affinity for water, unlike SO2. Its combination with water to form sulfuric acid is a highly exothermic process.

More

Upvote

VOTE

Downvote