In the reaction c + o2 —> co2 which element is reduced in the reaction? C O2 CO2
The Correct Answer and Explanation is:
In the reaction C + O₂ → CO₂, the element that is reduced is oxygen (O₂).
Explanation
To determine which element is reduced in a chemical reaction, we must look at the change in oxidation states of the elements involved. Oxidation is the loss of electrons, and reduction is the gain of electrons. A substance is reduced when it gains electrons, resulting in a decrease in oxidation state.
Let’s analyze each component of the reaction:
- Carbon (C) in its elemental form has an oxidation state of 0.
- Oxygen (O₂) in its molecular form also has an oxidation state of 0.
- In carbon dioxide (CO₂), carbon is bonded to two oxygen atoms. Each oxygen atom is more electronegative and usually has an oxidation state of -2. Since there are two oxygen atoms, the total negative charge is -4, which means carbon must have an oxidation state of +4 to balance the molecule to zero.
Now, let’s compare the changes:
- Carbon goes from 0 to +4, which means it loses electrons. Therefore, carbon is oxidized.
- Oxygen goes from 0 to -2, meaning it gains electrons. Therefore, oxygen is reduced.
Thus, oxygen is the element that is reduced in this reaction.
This reaction is a classic example of a redox reaction, where oxidation and reduction happen simultaneously. Carbon serves as the reducing agent because it donates electrons, while oxygen serves as the oxidizing agent because it accepts electrons.
Understanding redox reactions is critical in chemistry because they are involved in many biological and industrial processes such as cellular respiration, combustion, and corrosion. In combustion reactions like this one, a fuel (in this case, carbon) reacts with oxygen to form an oxide (carbon dioxide), releasing energy in the process. The transfer of electrons from carbon to oxygen is what drives the reaction forward.
