Answer : The equation represents a conservation of atoms is:
Explanation :
Law of conservation of matter : It states that matter can neither be created nor be destroyed but it can only be transformed from one form to another form.
The balanced chemical reaction always follow the law of conservation of matter.
Balanced chemical reaction : It is defined as the reaction in which the number of atoms of individual elements present on reactant side must be equal to the product side.
(1) The given chemical reaction is,
This reaction is a balanced chemical reaction in which number of atoms of iron and oxygen are equal on the both side of the reaction. So, this reaction obey the law of conservation of matter.
(2) The given chemical reaction is,
This reaction is an unbalanced chemical reaction in which number of atoms of iron and oxygen are not equal on the both side of the reaction. So, this reaction does not obey the law of conservation of matter.
(3) The given chemical reaction is,
This reaction is an unbalanced chemical reaction in which number of atoms of oxygen are not equal on the both side of the reaction. So, this reaction does not obey the law of conservation of matter.
Hence, the equation represents a conservation of atoms is: