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show all your work, box your answer, and use significant figures to receive credit.In the reaction for the combustion of methane, if 60.0 grams of carbon dioxide are produced, how many grams of steam (H2O gas) are also produced?

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Step-by-step explanation:

The equation fort the combustion reaction of methane is:

CH₄ + 2 O₂ ---> CO₂ + 2 H₂O

60.0 g of CO₂ are produced and we have to find the amount of H₂O that is also produced. First we have to convert the mass of CO₂ into moles using its molar mass.

molar mass of C = 12.01 g/mol

molar mass of O = 16.00 g/mol

molar mass of CO₂ = 1 * 12.01 g/mol + 2 * 16.00 g/mol

molar mass of CO₂ = 44.01 g/mol

moles of CO₂ = 60.0 g * 1 mol/(44.01 g)

moles of CO₂ = 1.36 moles

CH₄ + 2 O₂ ---> CO₂ + 2 H₂O

According to the coefficients of the equation, when 1 mol of CO₂ is produced, 2 moles of H₂O are also produced. We can use that ratio to find the number of moles of H₂O that are produced during our reaction.

1 mol of CO₂ : 2 moles of H₂O molar ratio

moles of H₂O = 1.36 moles of CO₂ * 2 moles of H₂O/(1 mol of CO₂)

moles of H₂O = 2.72 moles

And finally we can convert back to grams the moles of water using its molar mass.

molar mass of H = 1.01 g/mol

molar mass of O = 16.00 g/mol

molar mass of H₂O = 2 * 1.01 g/mol + 1 * 16.00 g/mol

molar mass of H₂O = 18.02 g/mol

mass of H₂O = 2.72 mol * 18.02 g/(1 mol)

mass of H₂O = 49.0 g

Answer: 49.0 g of steam are also produced.

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