Does `KI` salt on heating with concentrated H2SO4 ,Evolves coloured vapours?

Explanation

To determine whether potassium iodide (KI) salt evolves colored vapors when heated with concentrated sulfuric acid (H2SO4), we can follow these steps:

### Step-by-Step Solution:

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

2. **Write the Reaction**: When KI is heated with concentrated H2SO4, a chemical reaction occurs. The reaction can be represented as:
\[ 2 KI + H2SO4 \rightarrow K2SO4 + 2 HI \]
Here, potassium sulfate (K2SO4) and hydrogen iodide (HI) are formed.

3. **Analyze the Products**: After the initial reaction, the hydrogen iodide (HI) can further react with the concentrated sulfuric acid present in the solution. This can lead to the formation of iodine (I2):
\[ 2 HI + H2SO4 \rightarrow I2 + SO2 + H2O \]
In this reaction, iodine (I2) is produced.

4. **Observe the Characteristics of Iodine**: Iodine (I2) is known to produce colored vapors. Specifically, iodine vapor has a characteristic violet color.

5. **Conclusion**: Since the reaction produces iodine vapor, which is colored (violet), we can conclude that potassium iodide (KI) does indeed evolve colored vapors when heated with concentrated sulfuric acid.

### Final Answer:
Yes, potassium iodide (KI) salt on heating with concentrated H2SO4 evolves colored vapors, specifically violet iodine vapor (I2).

---