Question

Apply scientific knowledge and understanding to determine how many grams of carbon dioxide are produced from the combustion of 250. g of ethane, C3H8 when O2 is in excess:
C3H8 + 5O2 ---> 3CO2 + 4H2O

Answer 1

Answer:

749 grams CO₂

Explanation:

To find the amount of carbon dioxide produced, you need to (1) convert grams C₃H₈ to moles C₃H₈ (via molar mass from periodic table), then (2) convert moles C₃H₈ to moles CO₂ (via mole-to-mole ratio via reaction coefficients), and then (3) convert moles CO₂ to grams CO₂ (via molar mass from periodic table). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The desired unit should be in the numerator. The final answer should have 3 significant figures because the given value (250. grams) has 3 sig figs.

Molar Mass (C₃H₈): 3(12.01 g/mol) + 8(1.008 g/mol)

Molar Mass (C₃H₈): 44.094 g/mol

1 C₃H₈ + 5 O₂ ---> 3 CO₂ + 4 H₂O

Molar Mass (CO₂): 12.01 g/mol + 2(16.00 g/mol)

Molar Mass (CO₂): 44.01 g/mol

250. g C₃H₈         1 mole C₃H₈           3 moles CO₂              44.01 g
------------------  x  ----------------------  x  ----------------------  x  --------------------  =
                               44.094 g              1 mole C₃H₈            1 mole CO₂

= 749 grams CO₂