Kl when heated with conc .`H_2SO_4` , it forms

Options

A. `HIO_3`
B. `KIO_3`
C. `I_2`
D. HI

Answer

To solve the question of what Kl (potassium iodide) forms when heated with concentrated H2SO4 (sulfuric acid), let's break down the reaction step by step.

### Step 1: Identify the Reactants
The reactants in this reaction are potassium iodide (KI) and concentrated sulfuric acid (H2SO4).

### Step 2: Write the Initial Reaction
When potassium iodide is heated with concentrated sulfuric acid, the initial reaction can be represented as:
\[ \text{KI} + \text{H}_2\text{SO}_4 \rightarrow \text{KHSO}_4 + \text{HI} \]
This shows that potassium iodide reacts with sulfuric acid to form potassium hydrogen sulfate (KHSO4) and hydrogen iodide (HI).

### Step 3: Further Reaction of HI
The hydrogen iodide (HI) produced can further react with sulfuric acid. The reaction can be written as:
\[ \text{H}_2\text{SO}_4 + 2\text{HI} \rightarrow \text{I}_2 + \text{SO}_2 + 2\text{H}_2\text{O} \]
In this step, hydrogen iodide reacts with sulfuric acid to produce iodine (I2), sulfur dioxide (SO2), and water (H2O).

### Step 4: Identify the Products
From the reactions above, we can identify the products formed when potassium iodide is heated with concentrated sulfuric acid:
- Iodine (I2)
- Sulfur dioxide (SO2)
- Water (H2O)

### Conclusion
Thus, when potassium iodide (KI) is heated with concentrated sulfuric acid (H2SO4), it primarily forms iodine (I2) as a vapor, along with sulfur dioxide (SO2) and water (H2O).

The correct answer to the question is that it forms iodine (I2) as one of the products.

### Final Answer
The correct option is C: I2 (iodine).

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