In a 3L vessel, the following equilibrium partial pressures are measured; N2= 100  mm  of Hg,H2= 400  mm  of Hg and NH3= 1000  mm of Hg.Nitrogen is removed from the vessel at constant temperature until the pressure of hydrogen at equilibrium is equal to 700  mm of Hg . The new equilibrium partial pressure (in mm of Hg) of N2 is