Explanation:
According to Avogadro's law, equal volumes of all the gases at same temperature and pressure will also, have same number of molecules.
That is, [tex]V \propto n[/tex]
or [tex]\frac{V}{n}[/tex] = k
Since, it is given that [tex]V_{1}[/tex] is 6.13 L, [tex]n_{1}[/tex] is 8.51 mol, and [tex]V_{2}[/tex] is 18.5 L.
Hence, calculate the [tex]n_{2}[/tex] as follows.
[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]
[tex]\frac{6.13 L}{8.51 mol} = \frac{18.5 L}{n_{2}}[/tex]
[tex]{n_{2}}[/tex] = 0.35 mol
Thus, we can conclude that the number of moles of gas added to the container is 0.35 mol.