Answer: 8 moles
Step-by-step explanation:
C3H8(g) + 5O2(g) ---> 3CO2(g) + 4H2O(g)
The balanced equation above shows the combustion of propane, C3H8 (for x is 3; y is 8) in oxygen, O2 to yield carbon dioxide, CO2 and water, H2O
The mole ratio on combustion are as follows:
5 moles of O2 react to produce 3 moles of CO2
Z mole of O2 react to produce 4.8 moles of CO2
To get the value of Z, cross multiply
4.8 moles x 5 mole = 3 mole x Z
24 = 3Z
Divide both sides by 3
24/3 = 3Z/3
8 = Z
Thus, in the combustion of propane, 8 moles of oxygen (O2) are needed to react to produce 4.8 moles of carbon dioxide (CO2)