Question

4Fe + 3 O2 = 2 Fe203 represents:
1. an unbalanced equation
2. phase change
3. conservation of moles
4. conservation of atoms

Answer 1

That is a balanced equation, which involves in having the same number of totals atoms for each and every element in the left and right hand sides of the equation.
Therefore it is 3.

Answer 2

thanks so much