Given the balanced equation representing the reaction between methane and oxygen: CH4 + 2O2 → CO2 + 2H2O According to this equation, what is the mole ratio of oxygen to methane?
The Correct Answer and Explanation is:
Correct Answer:
The mole ratio of oxygen to methane is 2:1.
Explanation:
Chemical equations represent the quantitative relationships between reactants and products in a chemical reaction. The balanced equation for the combustion of methane is: CH4+2O2→CO2+2H2O\text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}CH4+2O2→CO2+2H2O
This equation indicates that one mole of methane (CH₄) reacts with two moles of oxygen (O₂) to produce one mole of carbon dioxide (CO₂) and two moles of water (H₂O). The coefficients in front of each chemical formula represent the number of moles involved in the reaction.
The mole ratio is determined by comparing the coefficients of the substances in question. In this case, the coefficient of oxygen (O₂) is 2, and the coefficient of methane (CH₄) is 1. Therefore, for every 1 mole of methane that reacts, 2 moles of oxygen are required. moles of O2moles of CH4=21\frac{\text{moles of } O_2}{\text{moles of } CH_4} = \frac{2}{1}moles of CH4moles of O2=12
Thus, the mole ratio of oxygen to methane is 2:1.
Mole ratios are essential in stoichiometry because they allow the calculation of the amount of one substance required or produced based on the amount of another substance. For example, if 5 moles of methane are burned, 10 moles of oxygen are needed, following the 2:1 ratio: 5 mol CH4×2 mol O21 mol CH4=10 mol O25 \, \text{mol CH}_4 \times \frac{2 \, \text{mol O}_2}{1 \, \text{mol CH}_4} = 10 \, \text{mol O}_25mol CH4×1mol CH42mol O2=10mol O2
Understanding mole ratios ensures accurate predictions of reactant consumption and product formation during chemical reactions.
