Question

The chemical equation provided shows iron rusting to form iron oxide. Use the drop-down menu to choose the coefficients that will balance the chemical equation.

()Fe + ()O2 → ()Fe2O3

Answer 1

`4 Fe + 3 O_2 \rightarrow 2 Fe_2 O_3`

Step-by-step explanation:

The original equation is:

`Fe + O_2 \rightarrow Fe_2 O_3`

We notice that:

- we have 1 atom of Fe on the left, and 2 atoms of Fe on the right

- we have 2 atoms of O on the left, and 3 atoms of O on the right

Therefore, the equation is not balanced.

In order to balance it, we can add:

- a coefficient 3 in front of
`O_2`

- a coefficient 2 in front of
`Fe_2 O_3`

So we have:

`Fe + 3 O_2 \rightarrow 2Fe_2O_3`

Now the oxygen is balanced, but the iron it not balanced yet, since we have 1 Fe on the left and 4 on the right. Therefore, we should add a coefficient 4 on the Fe on the left:

`4 Fe + 3 O_2 \rightarrow 2 Fe_2 O_3`