the balanced chemical equation for the reaction is as follows;
C₃H₈ + 5O₂ ---> 3CO₂ + 4H₂O
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
