When chlorine is bubbled through aqueous solution of potassium iodide, iodine gas is liberated because

Options

A. chlorine is more electropositive
B. chlorine has higher electron affinity
C. chlorine is more powerful oxidising agent than iodine.
D. none of the above

Answer

To understand why iodine gas is liberated when chlorine is bubbled through an aqueous solution of potassium iodide, we can analyze the reaction step by step.

### Step 1: Identify the Reactants
The reactants in this scenario are chlorine gas (Cl₂) and potassium iodide (KI) in an aqueous solution.

### Step 2: Understand the Reaction
When chlorine gas is introduced to the potassium iodide solution, a chemical reaction occurs. The potassium iodide dissociates in water to form potassium ions (K⁺) and iodide ions (I⁻).

### Step 3: Determine the Oxidation States
In the reaction:
- Chlorine (Cl₂) has an oxidation state of 0.
- Iodide (I⁻) has an oxidation state of -1.
- When iodine (I₂) is produced, it has an oxidation state of 0.

### Step 4: Write the Balanced Chemical Equation
The balanced chemical equation for the reaction can be written as:
\[ Cl_2 + 2KI \rightarrow 2KCl + I_2 \]

### Step 5: Analyze the Changes in Oxidation States
In this reaction:
- Chlorine (Cl) is reduced from 0 to -1 (it gains electrons).
- Iodide (I⁻) is oxidized from -1 to 0 (it loses electrons).

### Step 6: Identify the Oxidizing and Reducing Agents
- Chlorine acts as an oxidizing agent because it causes the iodide ions to lose electrons (oxidation).
- Iodine is reduced in this process.

### Step 7: Conclusion
Since chlorine is a more powerful oxidizing agent than iodine, it can effectively oxidize iodide ions to form iodine gas. Therefore, the correct answer to the question is that chlorine is more powerful oxidizing agent than iodine.

### Final Answer
Chlorine is more powerful oxidizing agent than iodine.

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