We’re being asked to determine which is the reactant in excess and determine the amount remaining if any.
For this problem, we need to do the following steps:
Step 1: Write and balance a chemical equation for the given reaction.
Step 2: Determine the limiting reactant and calculate the mass of CO2 formed.
Step 3: Calculate the remaining reactant in excess.
Step 1: We have a combustion reaction:
CH4 + O2 → CO2 + H2O
This equation is not yet balanced. To balance it, we have to make sure that the number of elements on both sides is equal.
Balance H: We have 4 H on the reactant side and 2 H on the product side – add a coefficient of 2 to H2O:
CH4 + O2 → CO2 + 2 H2O
Balance O: We have 2 O on the reactant side and 4 O on the product side – add a coefficient of 2 to O2:
CH4 + 2 O2 → CO2 + 2 H2O
Now that we have a balanced equation, we can determine how much CO2 is produced.
Imagine you mix 16.05 g of methane (CH4) gas and 96.00 g of oxygen (O2) gas and then ignite the mixture. After a bright flash and a loud bang, some water droplets form on the inside of the reaction vessel.
Will anything be left over? What? How much?