Assertion (A): Chlorine water has both oxidising as well as bleaching properties.
Reason (R): Chlorine reacts with water to evolve nascent oxygen.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not the correct explanation of A
C. A is true but R is false
D. A is false but R is true

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Chlorine water has both oxidizing as well as bleaching properties." To analyze this, we need to know what chlorine water is and how it behaves chemically.

2. **Chemical Composition of Chlorine Water**: Chlorine water is a solution of chlorine gas (Cl₂) in water (H₂O). When chlorine gas dissolves in water, it undergoes a reaction:
\[ Cl_2 + H_2O \rightarrow HCl + HClO \]
This reaction produces hydrochloric acid (HCl) and hypochlorous acid (HClO).

3. **Formation of Nascent Oxygen**: The hypochlorous acid formed can further decompose to release nascent oxygen (O). This nascent oxygen is highly reactive and is responsible for the oxidizing and bleaching properties of chlorine water.

4. **Oxidizing Properties**: Chlorine water acts as an oxidizing agent because it can accept electrons from other substances. For example, when chlorine water reacts with sulfur dioxide (SO₂):
\[ Cl_2 + SO_2 \rightarrow HCl + H_2SO_4 \]
In this reaction, sulfur is oxidized from +4 in SO₂ to +6 in H₂SO₄, indicating that chlorine is acting as an oxidizing agent.

5. **Bleaching Properties**: The nascent oxygen produced from chlorine water can react with colored organic substances, leading to their decolorization. This is the bleaching action of chlorine water, where it removes color from dyes and other pigments.

6. **Conclusion on Assertion**: Since chlorine water demonstrates both oxidizing and bleaching properties due to the presence of nascent oxygen, the assertion is true.

7. **Understanding the Reason**: The reason states that "Chlorine reacts with water to evolve nascent oxygen." This is indeed correct, as the reaction of chlorine with water leads to the formation of hypochlorous acid, which can release nascent oxygen.

8. **Conclusion on Reason**: The reason provided is a correct explanation for the assertion since the nascent oxygen produced is what gives chlorine water its oxidizing and bleaching properties.

9. **Final Evaluation**: Both the assertion and reason are true, and the reason correctly explains the assertion.

**Final Answer**: Both A and R are true, and R is the correct explanation of A.

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