Question

A mixture of N2 and H2 is caused to react in a
closed container to form NH3. The reaction ceases
before either reactant has been totally consumed.
At this stage, 2 moles each of N2, H2 and NH3
are present. Then the weight of N2 and H2 present
originally were respectively

Answer 1

N2+3H2⇌2NH3 

Initially moles   A              B             0 

At eq−b         A−x         B−x        2x

                     2x=2⇒x=1

                 A−x=2⇒A−1=2⇒A=3 

                B−3x=2⇒B−3=2,⇒B=5