Calculating the Mass of Propane Needed in a Chemical Reaction
Question:
What mass of propane (C3H8) is needed to produce 346 g carbon dioxide in the following reaction?
Answer:
The answer to this question is 115 grams.
Explanation:
Mass of CO2: 346 g
Molar mass of C3H8: 44 g/mole
Molar mass of CO2: 44 g/mole
First, we need to calculate the moles of CO2.
Moles of CO2 = Mass of CO2 / Molar mass of CO2 = 346g / 44g/mole = 7.86 moles
Next, we calculate the moles of C3H8 using the balanced chemical reaction:
C3H8 + 5O2 → 3CO2 + 4H2O
From the balanced reaction, we know that 3 moles of CO2 are obtained from 1 mole of C3H8.
So, 7.86 moles of CO2 react to give (1/3) × 7.86 = 2.62 moles of C3H8.
Now, we can calculate the mass of C3H8:
Mass of C3H8 = Moles of C3H8 × Molar mass of C3H8
Mass of C3H8 = 2.62 moles × 44 g/mole = 115.28g ≈ 115g
Therefore, the mass of propane needed to produce 346 g of carbon dioxide is 115 grams.