Which of the following is insoluble in water

Options

A. `Na_(2)CO_(3)`
B. `CaCO_(3)`
C. `ZnCO_(3)`
D. `Al_(2)(CO_(3))_(3)`

Explanation

To determine which of the given carbonates is insoluble in water, we will analyze the solubility of each compound listed: sodium carbonate (Na2CO3), calcium carbonate (CaCO3), zinc carbonate (ZnCO3), and aluminum carbonate (Al2(CO3)3).

### Step 1: Analyze the solubility of sodium carbonate (Na2CO3)
- Sodium carbonate is highly soluble in water. It dissociates completely into sodium ions (Na⁺) and carbonate ions (CO3²⁻) when dissolved.

**Hint:** Remember that most sodium salts are soluble in water.

### Step 2: Analyze the solubility of calcium carbonate (CaCO3)
- Calcium carbonate has low solubility in water. It does not dissolve well, and in fact, it forms a precipitate when mixed with water.

**Hint:** Consider the common uses of calcium carbonate, such as in chalk and limestone, which are not soluble in water.

### Step 3: Analyze the solubility of zinc carbonate (ZnCO3)
- Zinc carbonate is also poorly soluble in water. It has limited solubility and tends to form a precipitate.

**Hint:** Think about how zinc compounds behave in water; many are not very soluble.

### Step 4: Analyze the solubility of aluminum carbonate (Al2(CO3)3)
- Aluminum carbonate is considered to be insoluble in water. It does not dissolve and tends to form a precipitate.

**Hint:** Recall that aluminum compounds often have low solubility in water.

### Conclusion
Based on the analysis:
- Sodium carbonate is soluble.
- Calcium carbonate is poorly soluble but still somewhat soluble.
- Zinc carbonate is poorly soluble.
- Aluminum carbonate is mostly insoluble.

Therefore, the compound that is insoluble in water is **Aluminum Carbonate (Al2(CO3)3)**.

**Final Answer:** Aluminum Carbonate (Al2(CO3)3) is insoluble in water.