# Metal and non-metal oxides and water reaction?

1. Jan 21, 2013

### ASidd

1. The problem statement, all variables and given/known data
I understand how metallic oxide dissolve in water to produce OH- ion due to high electronegativity of oxygen. But I am having trouble understanding how non-metallic oxide dissolve in water to form acid?
For Homework I have to explain the reaction of Sulfur trioxide in water and how that produces H+ and sulfate ions.But I have no idea how to go on about this

2. Relevant equations3. The attempt at a solution

SO3 + H2O=> H2SO4
and H2SO4=> H+ +HSO4-
HSO4-=>H+ +SO4-

I have no idea if these are correct or not? Also what makes the H2SO4 in the first reaction disassociate to ions?

2. Jan 21, 2013

### Staff: Mentor

First and second equations are OK, the last one is not (charge is not balanced).

3. Jan 21, 2013

### ASidd

So h+ so4-==> h+ + so4-2?

4. Jan 21, 2013

### ASidd

I was also wondering when sulfur trioxide dissolves in water why does only one of the oxygen atoms in sulfur trioxide attaches to a hydrogen atom? why not the other 2

5. Jan 21, 2013

### Staff: Mentor

Can't say it is much better. Please pay attention to how you format these things - some letters have to be capitalized, some characters should be made subscripts/supperscripts and so on.

If you don't know how - [noparse]H3O+[/noparse] is displayed as H3O+.

H2SO4 is most stable for energetic reasons. Both HSO4- and H3SO4+ exist, although the latter is observed only in pure sulfuric acid, never in water solutions.

6. Jan 21, 2013

### ASidd

Okay thanks. Also do all non-metallic oxides have to be polar molecules in order to form an acid within water?

7. Jan 21, 2013

### Staff: Mentor

I wouldn't call CO2 polar.