I think it’s law conservation of mass.
So 200g(NH3)-47g(N2)=153g(H2)
H2+N2—->NH3
Answer is: D. Lewis base.
Lewis acid is a chemical element, molecule or ion that contains an empty orbital which is capable of accepting an electron pair from a Lewis base. A Lewis base is element, molecule or ion that has a filled orbital and has electron pair which is not involved in bonding and can give it to Lewis acid. Lewis base is for example ammonia (NH3).
