When a small amount of HCl is added to an aqueous solution of `BiCl_3` , a white precipitate is formed. This is due to formation of

Options

A. `Bi(OH)_3`
B. `Bi_2O_3`
C. `BiOCl`
D. None of the above

Answer

To solve the question, we need to analyze the reaction that occurs when hydrochloric acid (HCl) is added to an aqueous solution of bismuth(III) chloride (BiCl3). Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Reactants
We start with an aqueous solution of BiCl3. This compound is bismuth(III) chloride, which dissociates in water to form bismuth ions (Bi³⁺) and chloride ions (Cl⁻).

### Step 2: Reaction with Water
When BiCl3 is dissolved in water, it can react with water molecules. The reaction can be represented as:
\[ \text{BiCl}_3 + \text{H}_2\text{O} \rightarrow \text{BiOCl} + 2 \text{HCl} \]

### Step 3: Adding HCl
Now, when we add a small amount of HCl to this solution, the additional chloride ions (Cl⁻) from HCl do not further react with BiCl3. Instead, the reaction primarily leads to the formation of bismuth oxychloride (BiOCl), which is a sparingly soluble compound.

### Step 4: Formation of Precipitate
The compound BiOCl precipitates out of the solution as a white solid. This is the white precipitate referred to in the question.

### Step 5: Conclusion
Thus, the formation of the white precipitate is due to the formation of bismuth oxychloride (BiOCl).

### Final Answer
The correct answer is that the white precipitate formed is bismuth oxychloride (BiOCl).

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