A compound give violet flame rest and gives a white ppt with `AgNO_(3)` .The compound is

Options

A. `NaCI`
B. `KCI`
C. `BaCI_(2)`
D. `CaCI_(2)`

Answer

To determine the compound that gives a violet flame and a white precipitate with AgNO₃, we can follow these steps:

### Step 1: Identify the Flame Color
The first observation is that the compound gives a violet flame. In qualitative analysis, the flame test can help identify certain cations based on the color of the flame they produce.

- **Violet Flame**: The violet flame is characteristic of potassium ions (K⁺).

### Step 2: Identify the Reaction with AgNO₃
The second observation is that the compound gives a white precipitate when treated with silver nitrate (AgNO₃).

- **Reaction with AgNO₃**: When potassium chloride (KCl) is mixed with AgNO₃, it produces a white precipitate of silver chloride (AgCl):

\[ \text{KCl} + \text{AgNO}_3 \rightarrow \text{AgCl (s)} + \text{KNO}_3 \]

### Step 3: Conclusion
Based on the observations:
- The violet flame indicates the presence of potassium (K⁺).
- The white precipitate with AgNO₃ indicates the presence of chloride ions (Cl⁻).

Thus, the compound is potassium chloride (KCl).

### Final Answer
The compound is **KCl (Potassium Chloride)**.

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