Which of the following can work as oxidising agent ?

Explanation

To determine which compounds can act as oxidizing agents, we need to analyze their ability to gain electrons or increase their oxidation state. Here’s a step-by-step solution:

### Step 1: Understanding Oxidizing Agents
An oxidizing agent is a substance that can accept electrons in a chemical reaction. When it accepts electrons, it gets reduced, and in the process, it causes another substance to be oxidized.

### Step 2: Identifying Common Oxidizing Agents
Common oxidizing agents include:
- Hydrogen peroxide (H2O2)
- Potassium permanganate (KMnO4)
- Dichromate ions (Cr2O7^2-)
- Chlorine gas (Cl2)
- Nitric acid (HNO3)

### Step 3: Analyzing Hydrogen Peroxide (H2O2)
Hydrogen peroxide (H2O2) is a notable example. In H2O2, the oxidation state of oxygen is -1. It can act as an oxidizing agent by being reduced to water (H2O) or oxygen gas (O2).

- **Reduction to Water**:
\[ H2O2 + 2H^+ + 2e^- \rightarrow 2H2O \]

- **Reduction to Oxygen**:
\[ 2H2O2 \rightarrow 2H2O + O2 + 2e^- \]

### Step 4: Conclusion
Since H2O2 can gain electrons and cause other substances to be oxidized, it can function as both an oxidizing agent and a reducing agent.

### Final Answer
Among the compounds discussed, **H2O2** can work as an oxidizing agent.

---