The pressure exerted on walls of a 3L flask when 7g of ${\text{N}}_{\text{2}}$ is introduced

into it at 300K should be

Ideal gas equation is given in the below.

    $\text{PV}=\text{nRT}$

Then $\text{n}=\frac{\text{PV}}{\text{RT}}$

Mass of nitrogen${\text{N}}_{\text{2}}$ , m =7 g

Molar mass of nitrogen, MW = 28 g/mol

Number of moles of${\text{N}}_{\text{2}}$ , $n=\frac{\text{mass}\text{of}{\text{N}}_{\text{2}}}{\text{Molar}\text{mass}{\text{of N}}_{\text{2}}}$

                                           $n=\frac{7\text{g}}{28g/mol}=0.25\text{mol}$

Volume of flask , $\text{V}=\text{3}\text{L}$

Temperature , $\text{T}=\text{300}\text{K}$

Then, the pressure

$\text{P}=\frac{0.25\text{mol}\times 0.0821\text{L}\text{.atm}{\text{.mol}}^{-1}{\text{.K}}^{-1}\times 300\text{K}}{3\text{L}}=2.05\text{atm}$