Question

By now, you are familiar with enough chemical compounds to begin to write your own chemical reaction equations. Write two examples of what we mean by a combustion reaction.

Short answer

Example 1: Combustion of methane (CH4) yields the balanced equation: \(CH4 + 2O2 \rightarrow CO2 + 2H2O\) Example 2: Combustion of ethane (C2H6) yields the balanced equation: \(2C2H6 + 7O2 \rightarrow 4CO2 + 6H2O\)

Step-by-step solution

Combustion of methane (CH4)

Methane (CH4) is a common fuel used in combustion reactions. To balance the combustion reaction, we need to ensure that the number of atoms on the reactant side (fuel + oxidant) is equal to the number of atoms on the product side. The unbalanced equation for the combustion of methane is: CH4 + O2 -> CO2 + H2O To balance the equation: 1. Balance the carbon atoms: There is 1 carbon atom on both sides, so it is already balanced. 2. Balance the hydrogen atoms: There are 4 hydrogen atoms on the reactant side and 2 on the product side, so we need to add a coefficient of 2 to the water molecule: CH4 + O2 -> CO2 + 2H2O 3. Balance the oxygen atoms: There are now 4 oxygen atoms on the product side and 2 oxygen atoms on the reactant side, so we need to add a coefficient of 2 to the oxygen molecule: CH4 + 2O2 -> CO2 + 2H2O The balanced equation for the combustion of methane is: CH4 + 2O2 -> CO2 + 2H2O Example 2:

Combustion of ethane (C2H6)

Ethane (C2H6) is another common fuel used in combustion reactions. To balance the combustion reaction, we need to ensure that the number of atoms on the reactant side (fuel + oxidant) is equal to the number of atoms on the product side. The unbalanced equation for the combustion of ethane is: C2H6 + O2 -> CO2 + H2O To balance the equation: 1. Balance the carbon atoms: There are 2 carbon atoms on the reactant side, and 1 on the product side, so we need to add a coefficient of 2 to the carbon dioxide molecule: C2H6 + O2 -> 2CO2 + H2O 2. Balance the hydrogen atoms: There are 6 hydrogen atoms on the reactant side, and 2 on the product side, so we need to add a coefficient of 3 to the water molecule: C2H6 + O2 -> 2CO2 + 3H2O 3. Balance the oxygen atoms: There are now 7 oxygen atoms on the product side, and 2 on the reactant side, so we need to add a coefficient of 7/2 (3.5) to the oxygen molecule: C2H6 + 3.5O2 -> 2CO2 + 3H2O Since a balanced equation requires whole number coefficients, we can multiply the entire equation by 2 to obtain whole numbers: 2C2H6 + 7O2 -> 4CO2 + 6H2O (Balanced) The balanced equation for the combustion of ethane is: 2C2H6 + 7O2 -> 4CO2 + 6H2O