Obtaining Ratios from a Balanced Chemical Equation

Obtaining Ratios from a Balanced Chemical Equation 

The simplest combustible hydrocarbon—and therefore one of the simplest of all fuels—is methane, CH4. So the combustion of methane will provide a good place for us to begin our exploration of reaction stoichiometry. We start by writing a balanced chemical equation  

The physical state of the water formed in combustion will depend on the reaction conditions. 

As we discussed in Section 3.4, the coefficients in a chemical equation can be interpreted as molar relationships as well as molecular relationships. So we can say that the equation shows that one mole of methane reacts with two moles of oxygen to produce one mole of carbon dioxide and two moles of water. From the chemical equation, we can write the following set of mole ratios  

When doing stoichiometric calculations, mole ratios are very often written to look like fractions. They are used analogously to unit conversion factors, relating the amount of one substance to that of another  

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