Chemical Reaction Stoichiometry: Calculating the Mass of Benzene Required
How do you determine the mass of benzene required?
Given the following reaction:
2C₆H₆ + 15O₂ → 12CO₂ + 6H₂O
Calculate the mass of benzene, C₆H₆, required to produce 3.50 L of carbon dioxide gas, CO₂, at STP.
Calculating the Mass of Benzene Required:
First, we need to determine the moles of carbon dioxide gas, CO₂, produced at STP in the reaction. Details below:
At STP, 22.4 Liters = 1 mole of CO₂
Therefore, 3.5 liters of CO₂ = 3.5 / 22.4 = 0.156 moles of CO₂
Next, we calculate the moles of benzene, C₆H₆, required based on the balanced equation:
12 moles of CO₂ are obtained from 2 moles of C₆H₆
Hence, 0.156 moles of CO₂ will be produced from (0.156 × 2) / 12 = 0.026 moles of C₆H₆
Finally, we determine the mass of benzene, C₆H₆, required for the reaction:
- Moles of C₆H₆ = 0.026 moles
- Molar mass of C₆H₆ = 78 g/mol
- Mass of C₆H₆ = ?
Mass = Moles × Molar mass
Therefore, Mass of C₆H₆ = 0.026 × 78 = 2.028 grams
Hence, the mass of benzene, C₆H₆, required is 2.028 grams.
Explanation:
In stoichiometry, the mass of reactants and products can be calculated using balanced chemical equations and molar ratios. In this particular reaction, the conversion of liters of CO₂ to moles and further to the molar amount of benzene required allows us to determine the mass needed for the reaction.
By following the step-by-step process outlined above, we were able to calculate that 2.028 grams of benzene are necessary to produce 3.50 liters of CO₂ gas at STP. This type of calculation is essential in chemistry to ensure that reactions proceed efficiently and effectively based on the given quantities of reactants and products.
Understanding the principles of stoichiometry and being able to perform these calculations accurately is fundamental for predicting and analyzing chemical reactions in various scenarios.