At STP, a container has 1 mole of Ar, 2 moles of  ${CO}_2$, 3 moles of  $O_2$ and 4 moles of  $N_2$. Without changing the total pressure if one mole of $O_2$ is removed, the partial pressure of  $O_2$  is

The volume of gas $\mathrm{A}$ is twice than that of gas $\mathrm{B}$. The compressibility factor of gas $\mathrm{A}$ is thrice than that of gas $\mathrm{B}$ at same temperature. What are the pressures of the gases for equal number of moles?

'$\mathrm{x}$' $\mathrm{g}$ of molecular oxygen $\left({\mathrm{O}}_2\right)$ is mixed with $200 \mathrm{g}$ of neon $\left(\mathrm{Ne}\right)$. The total pressure of the nonreactive mixture of ${\mathrm{O}}_2$ and $\mathrm{Ne}$ in the cylinder is $25$ bar. The partial pressure of $\mathrm{Ne}$ is $20$ bar at the same temperature and volume. The value of '$\mathrm{x}$' is

[Given: Molar mass of ${\mathrm{O}}_2=32 \mathrm{g} {\mathrm{mol}}^{-1}$. Molar mass of $\mathrm{Ne}=20 \mathrm{g} {\mathrm{mol}}^{-1}$]

$2{\mathrm{SO}}_2( \mathrm{g})+{\mathrm{O}}_2( \mathrm{g})\to 2{\mathrm{SO}}_3( \mathrm{g})$ 

The above reaction is carried out in a vessel starting with partial pressure ${\mathrm{P}}_{{\mathrm{SO}}_2}=250 \mathrm{m} \mathrm{bar}$, ${\mathrm{P}}_{{\mathrm{O}}_2}=750 \mathrm{m} \mathrm{bar}$ and ${\mathrm{P}}_{{\mathrm{SO}}_3}=0 \mathrm{bar}$. When the reaction is complete, the total pressure in the reaction vessel is _____ $\mathrm{m} \mathrm{bar}$. 

(Round off of the nearest integer).