Question

C3H8 + O2 → CO2 + H2O

Answer 1

First, we'll balance the equation
C3H8 + 5O2 --> 3CO2 + 4H2O
Next, we know that a gas at stp occupies 22.4 liters/mole, so we can find the number of moles of oxygen gas.
15 liters O2 * (1 mole O2)/(22.4 liters O2) = 0.67 moles O2
Now we know from our balanced equation that there are 3 moles of CO2 per mole of O2, so we can find the number of moles of CO2 we produce.
0.67 moles O2 * (3 moles CO2/5 moles O2) = 0.40 moles CO2
Now, we have the number of moles of CO2, and we know that one mole occupies 22.4 liters, we can find the number of liters
.40 moles CO2 * (22.4 liters CO2)/(1 mole CO2) = 9.0 liters of CO2
The answer is D