Octane is a hydrocarbon that is found in gasoline. complete combustion of octane produces 8 l of carbon dioxide for every 9 l of water vapor (both measured at the same temperature and pressure). what is the ratio of carbon atoms to hydrogen atoms in a molecule of octane?

Explanation:

We start with the chemical equation for the combustion reaction of octane ().

The combustion reaction is as follows:

⇒

In this we need to consider some things:

So, when a molecule of octane combusts, 8 molecules of Carbon Dioxide and 9 molecules of water are created. We can see then that the coefficients in the chemical reaction (the numbers accompanying the chemical formula)  are proportional to moles and to volume.

Mathematically, the ratio of carbon atoms to hydrogen atoms would be , where x and y comes from , or , which simplified is