Which of the following is not a carbonate ore?

Options

A. Calamine
B. Siderite
C. Bauxite
D. Malachite

Answer

To determine which of the following is not a carbonate ore, we will analyze the chemical formulas of the given ores.

1. **Identify the ores and their formulas**:
- **Calamine**: The formula is \( \text{ZnCO}_3 \) (Zinc Carbonate).
- **Siderite**: The formula is \( \text{FeCO}_3 \) (Iron Carbonate).
- **Bauxite**: The formula is \( \text{Al}_2\text{O}_3 \cdot 2\text{H}_2\text{O} \) (Aluminum Oxide Hydrate).
- **Malachite**: The formula is \( \text{Cu}_2\text{CO}_3\text{(OH)}_2 \) (Copper Carbonate Hydroxide).

2. **Analyze the formulas**:
- **Calamine** contains the carbonate ion \( \text{CO}_3^{2-} \), so it is a carbonate ore.
- **Siderite** also contains the carbonate ion \( \text{CO}_3^{2-} \), so it is a carbonate ore.
- **Bauxite** does not contain the carbonate ion; instead, it contains aluminum oxide and water. Therefore, it is not a carbonate ore.
- **Malachite** contains the carbonate ion \( \text{CO}_3^{2-} \), so it is a carbonate ore.

3. **Conclusion**:
- Among the given options, **Bauxite** is the only one that is not a carbonate ore.

**Final Answer**: Bauxite is not a carbonate ore.

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