The molar mass of oxygen gas (O2) is 32.00 g/mol. The molar mass of C3H8 is 44.1 g/mol.

What mass of O2, in grams, is required to completely react with 0.025 g C3H8?

0.018

0.034

0.045

0.091

the balanced chemical equation for the reaction is as follows;

C ₃H₈ + 5O₂ - - - > 3CO₂ + 4H₂ O

stoichiometry of C₃H₈ to O₂ is 1:5

number of moles of C₃H₈ reacted - 0.025 g / 44.1 g/mol = 0.000567 mol according to molar ratio of 1:5

number of O₂ moles required are 5 times the amount of C₃H₈ moles reacted therefore number of O₂ moles required - 0.000567 x 5 = 0.00284 mol.

mass of O₂ required - 0.00284 mol x 32.00 g/mol = 0.091 mol.

answer is 0.091 mol