High School

If 37.9 grams of methane burn in the presence of 87.0 grams of oxygen, how many grams of carbon dioxide will be formed?

Answer :

Carbon dioxide formation involves 59.84 grams from this reaction.

  1. Write the balanced chemical equation for the combustion of methane:

CH₄ + 2O₂ → CO₂ + 2H₂O

  1. Calculate the moles of each reactant:

Molecular weight of methane (CH₄):

12 + 4(1) = 16 g/mol

Moles of CH₄ = 37.9 g / 16 g/mol

= 2.37 mol

Molecular weight of oxygen (O₂):

2(16) = 32 g/mol

Moles of O₂ = 87.0 g / 32 g/mol

= 2.72 mol

  1. Determine the limiting reactant:

The balanced equation shows 1 mole of CH₄ reacts with 2 moles of O₂.

Therefore, 2.37 moles of CH₄ would need 4.74 moles of O₂ to fully react.

Since we only have 2.72 moles of O₂, O₂ is the limiting reactant.

  1. Calculate the moles of CO2 produced:

According to the balanced equation, 2 moles of O₂ produce 1 mole of CO₂.

Thus, 2.72 moles of O₂ will produce:

Moles of CO₂ = 2.72 moles O2 × (1 mole CO₂/ 2 moles O₂)

= 1.36 moles CO₂

  1. Convert moles of CO₂ to grams:

Molecular weight of CO₂ = 12 + 2(16)

= 44 g/mol

Grams of CO₂ = 1.36 moles × 44 g/mol

= 59.84 grams