What is the oxidising agent in chlorine water ?

Options

A. HCl
B. `HClO_2`
C. HOCl
D. None of these

Answer

To determine the oxidizing agent in chlorine water, we can follow these steps:

### Step 1: Understand the Composition of Chlorine Water
Chlorine water is a solution of chlorine gas (Cl₂) in water (H₂O). The chemical reaction can be represented as:
\[ \text{Cl}_2 + \text{H}_2\text{O} \rightarrow \text{HCl} + \text{HOCl} \]

### Step 2: Identify the Oxidizing Agent
An oxidizing agent is a substance that causes oxidation by accepting electrons from another substance. In this case, we need to identify which species in the reaction is capable of oxidizing another substance.

### Step 3: Analyze the Products
From the reaction, we have two products: hydrochloric acid (HCl) and hypochlorous acid (HOCl). Among these, we need to determine which one acts as an oxidizing agent.

### Step 4: Determine the Role of HOCl
Hypochlorous acid (HOCl) is known to be a strong oxidizing agent. It can donate nascent oxygen (O) to other substances, which is a characteristic of oxidizing agents. This means that HOCl can oxidize other substances while itself being reduced.

### Step 5: Conclusion
Since HOCl donates oxygen and facilitates oxidation, it is identified as the oxidizing agent in chlorine water.

Thus, the correct answer is:
**HOCl (Hypochlorous acid)** is the oxidizing agent in chlorine water.

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