C not sure 100 percent but my best guess
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced equation will be:

Answer:
Due to the lack of context for your question I’m not completely sure which you are talking about but NH can be Imidogen or it could be ammonium which is NH4^1+