# In the formation of carbon dioxide from carbon monoxide and oxygen, how many liters of carbon monoxide, CO, are needed to react completely with 1/2 mole of oxygen gas at STP? 2 CO (g) + O2(g) → 2 CO2 (g)

Apr 16, 2016

Approx. $22.4$ $L$ of $C \equiv O$ gas are required.

#### Explanation:

At constant pressure and temperature, the volume of a gas represents the number of particles. You have given te stoichiometric equation:

$2 C \equiv O \left(g\right) + {O}_{2} \left(g\right) \rightarrow 2 C {O}_{2} \left(g\right)$,

And this equation shows that carbon monoxide reacts with molecular oxygen in a $2 : 1$ ratio. But at $S T P$, the volume of half a mole ${O}_{2}$ is $11.2 \cdot L$. And of course we need double the molar quantity, and thus double the volume, of carbon monoxide gas for stoichiometric reaction.