# What is the balanced equation of SO2 + O2 = SO3?

##### 1 Answer

The balanced equation is

#### Explanation:

You follow a systematic procedure to balance the equation.

Start with the unbalanced equation:

A method that often works is to balance everything other than

Another useful procedure is to start with what looks like the most complicated formula.

The most complicated formula looks like

**Balance #"S"#:**

We have

**Balance #"O"#:**

We have

Most instructors don't allow fractions in balanced chemical equations, because you can't have a fraction of an atom or a molecule.

To get rid of the fractions, you multiply all the coefficients by 2 and get

Now you can balance the equation by putting a 1 in front of the

We should now have a balanced equation.

Check to make sure:

The balanced equation is