Question

The combustion of a propane may be described by the chemical equation, C3H8(g) + 5O2(g) = 3CO2(g) + 4H2O(g)
How many grams of O2(g) are needed to completely burn 77.3 grams of C3H8(g)?

Answer 1

You need to convert grams of C3H8 to gmoles of C3H8. Then you would multiply this number times 5 (this being the conversion factor between O2 and C3H8) to find the moles of O2. Then convert the moles of O2 to grams of O2 to find how many grams of O2 are needed to compleletly burn 77.3 grams of C3H8.

Answer 2

Thank you! How do I find the conversion factor for future problems like this?

Answer 3

The conversion factor is the coefficients of the components in the balanced reaction.