Which equation Best obeys the law of conservation of mass? a) N2 + 3H2 —> 2NH3
b) H2 + O2 —> 2H20
c) 2Ag20 —> Ag2 + O2
d) N2 + H2 —> NH3

N₂   + 3H₂  →  2NH₃

Explanation:

To obey the law of conservation of mass, the number of atoms on both sides of the expression, must be the same.

According to the law of conservation of mass "in a chemical reaction, matter is neither created nor destroyed but changed from one form to another".

To express this in chemical reaction, the number of atoms must be the same in going from reactants to products.

                      N₂   + 3H₂  →  2NH₃

We have 2 atoms of Nitrogen on both sides of the expression.

Also, we have 6 atoms of hydrogen on both sides.