`underset("(mixture of two anions)")A underset("excess of "BaCl_2)overset("Cold")to"white ppt."overset"filtered"to"(Filtrate)" overset"boil"to"White ppt"darr`
Anion of (A) could be :

Options

A. `SO_(3)^(2-), HSO_(3)^(-)`
B. `CO_(3)^(2-), SO_(3)^(2-)`
C. `SO_(3)^(2-), HCO_(3)^(-)`
D. None of these

Answer

To solve the problem, we need to identify the two anions present in the mixture (A) based on the reactions described. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Reaction with Barium Chloride
When the mixture of two anions (A) is treated with excess barium chloride (BaCl₂) in cold conditions, a white precipitate is formed. This indicates that at least one of the anions must form an insoluble barium salt.

**Hint:** Consider common anions that form insoluble barium salts.

### Step 2: Identify Possible Anions
The two common anions that can form white precipitates with barium ions are:
- Sulfite ion (SO₃²⁻), which forms barium sulfite (BaSO₃).
- Bicarbonate ion (HCO₃⁻), which forms barium bicarbonate (Ba(HCO₃)₂) that is soluble in cold water.

**Hint:** Think about the solubility rules for barium salts to identify which anions might be present.

### Step 3: Analyze the Precipitate Formation
When barium sulfite (BaSO₃) is formed, it is a white precipitate. Barium bicarbonate (Ba(HCO₃)₂) remains in solution. Thus, the residue after filtration will be barium sulfite, and the filtrate will contain barium bicarbonate.

**Hint:** Remember that the residue is the solid left behind after filtration, while the filtrate is the liquid that passes through.

### Step 4: Boil the Filtrate
Upon boiling the filtrate (barium bicarbonate), it decomposes to form barium carbonate (BaCO₃), which is also a white precipitate, along with the release of water (H₂O) and carbon dioxide (CO₂) gas.

**Hint:** Consider the thermal decomposition reactions of bicarbonates.

### Step 5: Conclude the Anions Present
Based on the above reactions, we can conclude that the two anions present in the mixture (A) are:
1. Sulfite ion (SO₃²⁻)
2. Bicarbonate ion (HCO₃⁻)

Thus, the anion of (A) could be a mixture of sulfite and bicarbonate ions.

### Final Answer
The anions of (A) could be: **Sulfite ion (SO₃²⁻) and Bicarbonate ion (HCO₃⁻)**.

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