A cylinder was filled with gaseous mixture containing CO and N₂ (equal masses). The ratio of their partial pressures in cylinder is:

PN₂, = P_T x mole fraction of N₂
Pco =  P_T x mole fraction of CO
$\therefore \frac{{\mathrm{P}}_{{\mathrm{N}}_2}^{\mathrm{\prime }}}{{\mathrm{P}}_{\mathrm{CO}}^{\mathrm{\prime }}}=\frac{\text{ Mole fraction of }{\mathrm{N}}_2}{\text{ Mole fraction of }\mathrm{CO}}=\frac{\text{ Mole of }{\mathrm{N}}_2}{\text{ Mole of }\mathrm{CO}}=\frac{\mathrm{w}/28}{\mathrm{w}/28}=1:1$