Chlorine water loses its yellow colour on standing because :

Options

A. HCl gas is produced, due to the action of sunlight.
B. a mixture of HOCl and HCl is produced in the presence of light.
C. HOCl and hydrogen gas is produced
D. a mixture of HCl and `ClO_(3)` is produced, due to the action of sunlight

Explanation

To solve the question "Chlorine water loses its yellow color on standing because:", we can break it down into several steps.

### Step-by-Step Solution:

1. **Understanding Chlorine Water**: Chlorine water is a solution of chlorine gas (Cl₂) dissolved in water. It has a yellowish color due to the presence of chlorine.

2. **Reaction of Chlorine with Water**: When chlorine water is allowed to stand, it undergoes a chemical reaction with water. The reaction can be represented as:
\[ \text{Cl}_2 + \text{H}_2\text{O} \rightarrow \text{HClO} + \text{HCl} \]
Here, chlorine reacts with water to form hypochlorous acid (HClO) and hydrochloric acid (HCl).

3. **Role of Sunlight**: This reaction is facilitated by sunlight, which helps in the dissociation of chlorine into its components.

4. **Further Dissociation of Hypochlorous Acid**: The hypochlorous acid (HClO) can further dissociate to produce nascent oxygen (O) and hydrochloric acid (HCl):
\[ \text{HClO} \rightarrow \text{HCl} + \text{O} \]
Nascent oxygen is highly reactive and can combine with another nascent oxygen to form molecular oxygen (O₂), which is colorless.

5. **Color Change**: As the yellowish chlorine gas is converted into colorless products (HCl and O₂), the solution loses its yellow color over time.

6. **Conclusion**: Therefore, the yellow color of chlorine water diminishes due to the formation of a mixture of hypochlorous acid (HClO) and hydrochloric acid (HCl) in the presence of sunlight, leading to the production of colorless oxygen.

### Final Answer:
Chlorine water loses its yellow color on standing because a mixture of hypochlorous acid (HClO) and hydrochloric acid (HCl) is produced in the presence of sunlight.

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