# Mass-to-Mass Conversions in Stoichiometry

The coefficients in a balanced chemical equation provide the mole-to-mole stoichiometry among the reactants and products. The molar mass (in g/mol) can be used as the conversion factor between moles and the mass of a substance.  Thus, the balanced equation and molar masses can be used in conjunction with one another to calculate the masses involved in a reaction.

When methane (CH4) burns, it reacts with oxygen gas to produce carbon dioxide and water. The unbalanced equation for this reaction is

CH4(g)+O2(g)→CO2(g)+H2O(g)

This type of reaction is referred to as a complete combustion reaction.

What coefficients are needed to balance the equation for the complete combustion of methane? Enter the coefficients in the order CH4, O2, CO2, and H2O, respectively.

What mass of carbon dioxide is produced from the complete combustion of 7.20×10−3g of methane?

What mass of water is produced from the complete combustion of 7.20×10−3g of methane?

What mass of oxygen is needed for the complete combustion of 7.20×10−3g of methane?