Which of the following react with dil `H_(2)SO_(4)`?

Options

A. `CaCO_(3)`
B. `KNO_(2)`
C. `Na_(2)S`
D. `BaCl_(2)`

Explanation

To determine which of the given compounds react with dilute H₂SO₄ (sulfuric acid), we will analyze each option step by step.

### Step 1: Analyze Calcium Carbonate (CaCO₃)
- **Reaction**: When calcium carbonate reacts with dilute sulfuric acid, it produces calcium sulfate (CaSO₄), water (H₂O), and carbon dioxide (CO₂).
- **Equation**:
\[ \text{CaCO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{CaSO}_4 + \text{H}_2\text{O} + \text{CO}_2 \]
- **Conclusion**: Calcium carbonate reacts with dilute H₂SO₄.

### Step 2: Analyze Potassium Nitrite (KNO₂)
- **Reaction**: Potassium nitrite reacts with dilute sulfuric acid to form potassium sulfate (K₂SO₄), nitrogen dioxide (NO₂), nitric oxide (NO), and water (H₂O).
- **Equation**:
\[ 3\text{KNO}_2 + 3\text{H}_2\text{SO}_4 \rightarrow \text{K}_2\text{SO}_4 + 2\text{NO}_2 + \text{NO} + 3\text{H}_2\text{O} \]
- **Conclusion**: Potassium nitrite reacts with dilute H₂SO₄.

### Step 3: Analyze Sodium Sulfide (Na₂S)
- **Reaction**: Sodium sulfide reacts with dilute sulfuric acid to produce sodium sulfate (Na₂SO₄) and hydrogen sulfide gas (H₂S).
- **Equation**:
\[ \text{Na}_2\text{S} + \text{H}_2\text{SO}_4 \rightarrow \text{Na}_2\text{SO}_4 + \text{H}_2\text{S} \]
- **Conclusion**: Sodium sulfide reacts with dilute H₂SO₄.

### Step 4: Analyze Barium Chloride (BaCl₂)
- **Reaction**: Barium chloride reacts with dilute sulfuric acid to form barium sulfate (BaSO₄) and hydrochloric acid (HCl).
- **Equation**:
\[ \text{BaCl}_2 + \text{H}_2\text{SO}_4 \rightarrow \text{BaSO}_4 + 2\text{HCl} \]
- **Conclusion**: Barium chloride reacts with dilute H₂SO₄.

### Final Conclusion
All four compounds (calcium carbonate, potassium nitrite, sodium sulfide, and barium chloride) react with dilute H₂SO₄.

### Summary of Reactions
1. CaCO₃ + H₂SO₄ → CaSO₄ + H₂O + CO₂ (reacts)
2. KNO₂ + H₂SO₄ → K₂SO₄ + NO₂ + NO + H₂O (reacts)
3. Na₂S + H₂SO₄ → Na₂SO₄ + H₂S (reacts)
4. BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl (reacts)