Through ratio and proportion, for every mole of O2, there is also a mole equivalent of CO2. In this case, we divide first 8.94 g O2 by 32 g/mol to convert the mass to mole. That is equivalent to 0.279375 mol which is also the amount of CO2. Multiplied by 44g/mol which is the molar mass of CO2, the answer is 12.29 grams CO2.
