CHEMISTRY HELP?

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2016-06-13 4:21 am

18. One disadvantage of burning propane (C3H8) is that carbon dioxide is one of the products. The released carbon dioxide increases the amount of CO2 in the atmosphere and increases the effects of global warming. How many grams of CO2 would you say is produced when 11.98 grams of propane is burned in excess oxygen in a gas grill?

19. Molten iron and carbon monoxide are produced in a blast furnace by the reaction of iron(III) oxide and coke (carbon). If 17.86 grams of pure Fe2O3 are used, how many grams of iron can be produced?

回答 (1)

fooks

2016-06-13 5:17 am

✔ 最佳答案

18.
Molar mass of C₃H₈ = (12.01×3 + 1.008×8) g/mol = 44.09 g/mol
Molar mass of CO₂ = (12.01 + 16.00×2) g/mol = 44.01 g/mol

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

No. of moles of C₃H₈ reacted = (11.98 g) / (44.09 /mol)
No. of moles of CO₂ produced = [(11.98 g) / (44.09 /mol)] × 3
Mass of CO₂ produced = [(11.98 g) / (44.09 /mol)] × 3 × (44.01 g/mol) = 35.87 g

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19.
Molar mass of Fe = 55.85 g/mol
Molar mass of Fe₂O₃ = (55.85×2 + 16.00×3) = 159.70 g/mol

Fe₂O₃ + 3C → 2Fe + 3CO

No. of moles of Fe₂O₃ reacted = (17.86 g) / (159.70 g/mol)
No. of moles of Fe produced = [(17.86 g) / (159.70 g/mol)] × 2
Mass of Fe produced = [(17.86 g) / (159.70 g/mol)] × 2 × (55.85 g/mol) = 12.49 g

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