The reaction that takes place when `Cl_(2)` gas is passed through conc NaOH solution is

Options

A. Oxidation
B. Reduction
C. Displacement
D. Disproportionation

Explanation

To determine the reaction that takes place when chlorine gas (Cl₂) is passed through concentrated sodium hydroxide (NaOH) solution, we can follow these steps:

### Step 1: Write the Reaction
When Cl₂ gas reacts with concentrated NaOH, the products formed are sodium chloride (NaCl), sodium chlorate (NaClO₃), and water (H₂O). The balanced chemical equation for this reaction is:

\[ 6 \text{NaOH} + 3 \text{Cl}_2 \rightarrow 5 \text{NaCl} + \text{NaClO}_3 + 3 \text{H}_2\text{O} \]

### Step 2: Identify Oxidation States
Next, we need to determine the oxidation states of chlorine in the reactants and products:

- In Cl₂, the oxidation state of chlorine is 0.
- In NaCl, the oxidation state of chlorine is -1 (since Na is +1).
- In NaClO₃, we can calculate the oxidation state of chlorine:
- Let the oxidation state of Cl be x.
- The equation will be: \( x + 3(-2) = 0 \)
- Thus, \( x - 6 = 0 \) → \( x = +5 \)

### Step 3: Determine Oxidation and Reduction
From the oxidation states:
- Chlorine in Cl₂ (0) is reduced to NaCl (-1).
- Chlorine in NaClO₃ (+5) is oxidized from Cl₂ (0).

### Step 4: Identify the Type of Reaction
Since the same element (chlorine) undergoes both oxidation and reduction, this reaction is classified as a disproportionation reaction.

### Conclusion
The reaction that occurs when Cl₂ gas is passed through concentrated NaOH solution is a **disproportionation reaction**.

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