Question

Which of the following is not a reducing agent?

• A. SO₂
• B. H₂O₂
• C. CO₂
• D. Al

Hint:

A reducing agent causes reduction by losing electrons; hence it gets oxidized.

Answer 1

The Correct Option is C

To determine which among the given options is not a reducing agent, we need to consider the chemical nature and typical reactions of each compound.

1. SO₂ (Sulfur Dioxide): Sulfur dioxide acts as a reducing agent because it can donate electrons to oxidize other substances. For example, in reactions such as the conversion of chromate ions to chromium ions, SO₂ is oxidized to sulfate. Therefore, SO₂ is a reducing agent.
2. H₂O₂ (Hydrogen Peroxide): Hydrogen peroxide can function both as an oxidizing and a reducing agent depending on the reaction conditions. In contexts of reduction, it can give electrons to substances like permanganate. So, under different conditions, it can act as a reducing agent.
3. CO₂ (Carbon Dioxide): Carbon dioxide is generally a product of combustion and is stable, showing no tendency to donate electrons and reduce other substances. It is a fully oxidized state of carbon, and under normal circumstances, CO₂ does not act as a reducing agent.
4. Al (Aluminum): Metallic aluminum is a strong reducing agent. It readily donates electrons to transform into Al³⁺ ions. It is frequently used in reactions requiring a strong reducing agent, like the thermite reaction.

From this analysis, we can conclude that CO₂ is not a reducing agent. Unlike other substances listed, CO₂ does not have the propensity to lose electrons under typical conditions due to its highly oxidized state. Thus, the correct answer is CO₂.