While sulphate dioxide and hydrogen peroxide can act as oxidising as well as reducing agents in their reactions, ozone and nitric acid act only as oxidants. Why?

Explanation

To answer the question regarding why sulfur dioxide (SO2) and hydrogen peroxide (H2O2) can act as both oxidizing and reducing agents, while ozone (O3) and nitric acid (HNO3) can only act as oxidizing agents, we can follow these steps:

### Step 1: Understanding Oxidizing and Reducing Agents
- An **oxidizing agent** is a substance that oxidizes another species and itself gets reduced. This means it gains electrons.
- A **reducing agent** is a substance that reduces another species and itself gets oxidized. This means it loses electrons.

### Step 2: Analyzing Sulfur Dioxide (SO2)
- The oxidation state of sulfur in SO2 is +4.
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