Question

A major component of gasoline is octane, C8H18. When octane is burned in air, it chemically reacts with oxygen gas (O2) to produce carbon dioxide (CO2) and water (H2O) . What mass of carbon dioxide is produced by the reaction of 3.2g of oxygen gas? Round your answer to 2 significant digits.

Answer 1

Answer:

$m_{CO_2}=2.8gCO_2$

Explanation:

Hello,

In this case, the combustion of octane is chemically expressed by:

$C_8H_{18}+\frac{25}{2} O_2\rightarrow 8CO_2+9H_2O$

In such a way, due to the 25/2:8 molar ratio between oxygen and carbon dioxide, we can compute the yielded grams of carbon dioxide (molar mass 44 g/mol) as shown below:

$m_{CO_2}=3.2gO_2*\frac{1molO_2}{32gO_2} *\frac{8molCO_2}{\frac{25}{2}molO_2 } *\frac{44gCO_2}{1molCO_2}\\ \\m_{CO_2}=2.8gCO_2$

Best regards.