# What is the chemical formula of sulphur trioxide?

Jan 27, 2017

Sulfur trioxide - $S {O}_{\text{3}}$.

#### Explanation:

Sulfur trioxide: $S {O}_{\text{3}}$.

How I came to this conclusion:

I noticed that the compound consists of non-metals, therefore it must be a covalent compound - meaning I use prefixes for compounds.

Sulfur is $S$. Simple enough. Trioxide has the prefix of tri, meaning "3". Therefore there is 3 atoms of oxygen. Combine them and I get $S {O}_{\text{3}}$.

Don't be confused with sulfite: ${\left(S {O}_{\text{3}}\right)}^{2 -}$ and sulfate: ${\left(S {O}_{\text{4}}\right)}^{2 -}$

Hope this helps :)