Question

Iron reacts with oxygen to produce iron oxide (rust). This reaction is represented in an equation as 4Fe + xO2 → 2Fe2O3. Identify the value of x that will balance the equation.

ANSWERS

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2
3
4

Answer 1

The balanced chemical equation for iron reacting with oxygen to produce iron oxide is 4Fe + 3O2 → 2Fe2O3, so the value of x that balances the equation is 3.

Step-by-step explanation:

To balance the chemical equation for the reaction between iron and oxygen that produces iron oxide (rust), we must ensure that the number of atoms for each element is the same on both sides of the equation. The given equation is 4Fe + xO2 → 2Fe2O3. To balance the equation, we need to balance the number of oxygen atoms. Each molecule of Fe2O3 has 3 oxygen atoms, so 2 molecules have a total of 6 oxygen atoms. Thus, to provide the necessary 6 oxygen atoms, we need 3 molecules of O2 because each O2 molecule contains 2 oxygen atoms. Therefore, the balanced chemical equation is 4Fe + 3O2 → 2Fe2O3, which means the value of x is 3.

Answer 2

Answer is: the value of x is 3.

Chemical reaction: Fe + O₂ → Fe₂O₃.

Oxidation half reaction: Fe⁰ → Fe⁺³ + 3e⁻ /×4; 4Fe⁰ → 4Fe⁺³ + 12e⁻.

Reduction half reaction: O₂⁰+ 4e⁻ → 2O⁻²/×3; 3O₂⁰+ 12e⁻ → 6O⁻².

Balanced chemical reaction: 4Fe + 3O₂ → 2Fe₂O₃.

Oxidation is increase of oxidation number, iron is oxidized from oxidation number 0 (Fe) to oxidation number +3 (in rust Fe₂O₃).