Question

Can you put a higher reaction coefficient when balancing equations?

For example, for `SO_2 + O_2 -> SO_3` the balanced equation is `2SO_2 + O_2 -> 2SO_3` but can it also be `4SO_2 + O_2 -> 4SO_3` ?

Answer 1

Well we usually use the simplest whole number ratio.....

Explanation:

And thus we want....

`2SO_2 + O_2(g) rarr 2SO_3(g)`

But `4SO_2 + O_2(g) rarr 4SO_3(g)` IS CLEARLY unbalanced with respect to oxygen....Do you agree? And thus this cannot be accepted as a representation of chemical reality.

Some chemists like to introduce half-integral coefficients into the equation.

`SO_2(g) + 1/2O_2 rarr SO_3(g)`

Here, I find that the half-integral coefficient makes assessment of the stoichiometry, the arithmetic, a bit easier. Every stoichiometric equation MUST be absolutely balanced with respect to mass and charge.

And see this [old answer.](https://socratic.org/questions/h2-1-2-o2-h2o-is-it-right-or-not)

Answer 2

Yes, you can put all the reaction coefficient higher.

So, "...can it also be `4SO_2 + O_2 → 4SO_3`?"

No, it can't because the equation is not balanced respect to oxygen.

Explanation:

Once you have correctly balanced the equation:

`2SO_2 + O_2 → 2SO_3`

you can use any multiple of all coefficients, as in:

`4SO_2 + 2 O_2 → 4SO_3`, or in:
`6SO_2 + 3 O_2 → 6SO_3`, etc.

given that the equation remains balanced.