Answer:
53.6 grams O₂
Step-by-step explanation:
To find the amount of oxygen gas that is needed to carry out the reaction, you need to (1) convert the mass of ethane (C₂H₆) to moles (using the molar mass), then (2) convert moles C₂H₆ to moles O₂ (using the mole-to-mole ratio), and then (3) convert moles O₂ to grams (using the molar mass). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs like the given value (14.4 = 3 sig figs).
Atomic Mass (C): 12.011 g/mol
Atomic Mass (H): 1.008 g/mol
Atomic Mass (O): 15.999 g/mol
Molar Mass (C₂H₆): 2(12.011 g/mol) + 6(1.008 g/mol) = 30.07 g/mol
Molar Mass (O₂): 2(15.999 g/mol) = 31.998 g/mol
2 C₂H₆ + 7 O₂ -----> 4 CO₂ + 6 H₂O
^ ^
Mole-to-mole ratio = 2:7
14.4 g C₂H₆ 1 mole 7 moles O₂ 31.998 g
------------------- x ---------------- x ------------------------ x ---------------- = 53.6 g O₂
30.07 g 2 moles C₂H₆ 1 mole