A student wrote a chemical equation as shown. Fe2O3 + 3H2 → Fe + H2O

What should the student do to balance the equation?

A. Add a coefficient 2 before Fe and a 3 before H2O

B. Add a coefficient 3 before Fe and a 2 before H2O

C. Add a coefficient 4 before Fe and a 5 before H2O

D. Add a coefficient 5 before Fe and a 4 before H2O

Option A. Add a coefficient 2 before Fe and a 3 before H2O

Explanation:

Fe₂O₃ + 3H₂ —> Fe + H₂O

The above equation can be balance by as follow:

Fe₂O₃ + 3H₂ —> Fe + H₂O

There are 2 atoms of Fe on the left side and 1 atom on the right side. It can be balance by putting 2 before Fe as shown below:

Fe₂O₃ + 3H₂ —> 2Fe + H₂O

There are 3 atoms of O on the left side and 1 atom on the right side. It can be balance by putting 3 before H₂O as shown below:

Fe₂O₃ + 3H₂ —> 2Fe + 3H₂O

Now the equation is balanced.

Thus, the student should add a coefficient 2 before Fe and a 3 before H2O

the answer is d. 74.02