A cylindrical container of volume $4.0 \times 10^{-3} \mathrm{~m}^3$ contains one mole of hydrogen and two moles of carbon dioxide. Assume the temperature of the mixture is 400 K . The pressure of the mixture of gases is : [Take gas constant as $\left.8.3 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right]$