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

4Fe + 3O2 → 2Fe2O3 <or> The chemical formula for rust is Fe2O3. Rust is formed when iron reacts with oxygen in moist air. The following chemical equation represents the reaction: 4Fe + 3O2 → 2Fe2O3. Water is necessary for the oxidation reaction to occur and to facilitate transport of the electrons.

Answer 2

Answer: The balanced chemical equation is $4Fe(s)+3O_2(g)\rightarrow 2Fe_2O_3(s)$

Explanation:

Rust is reddish-brown coating on iron metal which is formed when iron comes in contact with air and moisture to form ferric oxide. The chemical formula for trust is $Fe_2O_3$ and chemical name is ferric oxide.

The balanced chemical equation for the formation of rust follows:

$4Fe(s)+3O_2(g)\rightarrow 2Fe_2O_3(s)$

By Stoichiometry of the reaction:

4 moles of iron metal reacts with 3 moles of oxygen gas to produce 2 moles of ferric oxide.

Hence, the coefficients are 4, 3 and 2.