For a gaseous phase reaction A(g)+3B(g)⇌2C(g) , initial pressure is 600 mm at 1  : 2 molar ratio of A and B. If the equilibrium pressure of A is 100mm, that of B & C respectively are (in mm)

A         +         3B          ⇌    2C 200              400                 0 (200−x) (400−3x)       2x Given that 200−x=100            x=100 Initial pressure of A=13  ×  600=200  mm Initial pressure of B=23×600=400  mm ∴  Eq. pressure of C=2x=200  mm ∴  Eq. pressure of B=400−3x=100  mm