In the isolation of metals, calcination process usually results in:

Options

A. Metal oxide
B. Metal carbonate
C. Metal sulphide
D. Metal hydroxide

Answer

To solve the question regarding the calcination process in the isolation of metals, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Process of Calcination**:
- Calcination is a thermal treatment process in which ores are heated in the absence of air or in a limited supply of air. This process is primarily used for carbonate ores.

2. **Identify the Products of Calcination**:
- During calcination, carbonate ores decompose to form metal oxides and carbon dioxide gas. The general reaction can be represented as:
\[ \text{Metal Carbonate} \rightarrow \text{Metal Oxide} + \text{Carbon Dioxide} \]

3. **Example Reaction**:
- For instance, if we take zinc carbonate (ZnCO3) as an example, the reaction during calcination would be:
\[ \text{ZnCO}_3 \, (s) \rightarrow \text{ZnO} \, (s) + \text{CO}_2 \, (g) \]
- Here, zinc oxide (ZnO) is the metal oxide produced, and carbon dioxide (CO2) is released as a gas.

4. **Conclusion**:
- From the above understanding, we can conclude that the calcination process results in the formation of metal oxides from carbonate ores.

5. **Select the Correct Option**:
- Based on the information gathered, the correct answer to the question is that the calcination process usually results in **metal oxides**.

### Final Answer:
The calcination process usually results in **metal oxides**.

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