Answer : The volume of the sample after the reaction takes place is, 15.93 liters.
Explanation : Given,
Moles of [tex]N_2[/tex] = 0.13 mole
Moles of [tex]O_2[/tex] = 0.26 mole
Initial volume of gas = 23.9 L
First we have to calculate the moles of [tex]NO_2[/tex] gas.
The balanced chemical reaction is :
[tex]N_2(g)+2O_2(g)\rightarrow 2NO_2(g)[/tex]
From the balanced reaction, we conclude that
As, 1 mole of [tex]N_2[/tex] react with 2 moles of [tex]O_2[/tex] to give 2 moles of [tex]NO_2[/tex].
So, 0.13 mole of [tex]N_2[/tex] react with [tex]2\times 0.13=0.26[/tex] moles of [tex]O_2[/tex] to give [tex]2\times 0.13=0.26[/tex] moles of [tex]NO_2[/tex].
According to the Avogadro's Law, the volume of the gas is directly proportional to the number of moles of the gas at constant pressure and temperature.
[tex]V\propto n[/tex]
or,
[tex]\frac{V_1}{V_2}=\frac{n_1}{n_2}[/tex]
where,
[tex]V_1[/tex] = initial volume of gas = 23.9 L
[tex]V_2[/tex] = final volume of gas = ?
[tex]n_1[/tex] = initial moles of gas = 0.13 + 0.26 = 0.39 mole
[tex]n_2[/tex] = final moles of gas = 0.26 mole
Now put all the given values in the above formula, we get the final temperature of the gas.
[tex]\frac{23.9L}{V_2}=\frac{0.39mole}{0.26mole}[/tex]
[tex]V_2=15.93L[/tex]
Therefore, the volume of the sample after the reaction takes place is, 15.93 liters.