Which of the following reactions does not occur during calcination?

Options

A. `CaCO_(3)rarrCaO+CO_(2)`
B. `CuCo_(3).Cu(OH)_(2)rarr2CuO+H_(2)Odarr+CO_(2)darr`
C. `CuS+O_(2)rarrCuO+SO_(2)darr`
D. `CuSO_(4).5H_(2)OrarrCuSO_(4)+5H_(2)Odarr`

Explanation

To determine which of the following reactions does not occur during calcination, we first need to understand what calcination is and the types of ores involved in this process.

### Step-by-Step Solution:

1. **Definition of Calcination**:
- Calcination is a thermal treatment process where ores are heated in the absence of air or in a limited supply of air (oxygen). The primary purpose is to drive off volatile substances, such as water or carbon dioxide, and to convert the ore into its metal oxide form.

2. **Types of Ores Involved**:
- Calcination typically involves carbonate ores (e.g., calcium carbonate), hydroxides, and some sulfates. These ores decompose upon heating to form metal oxides and release gases.

3. **Reactions During Calcination**:
- For example, when calcium carbonate (CaCO₃) is calcined, it decomposes to form calcium oxide (CaO) and carbon dioxide (CO₂):
\[ \text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2 \uparrow \]
- Similarly, hydroxides and some sulfates undergo similar transformations.

4. **Sulfide Ores**:
- Sulfide ores (e.g., nickel sulfide) do not undergo calcination. Instead, they are roasted, which involves heating in the presence of excess air. This process converts sulfides to oxides and releases sulfur dioxide:
\[ \text{NiS} + \text{O}_2 \rightarrow \text{NiO} + \text{SO}_2 \uparrow \]

5. **Identifying the Correct Option**:
- Given the options, we need to identify which one represents a reaction that does not occur during calcination. Since sulfide ores are roasted and not calcinated, any option that mentions a sulfide ore would be the correct answer.

### Conclusion:
The reaction that does not occur during calcination is the one involving a sulfide ore, as it is heated in excess air (roasting) rather than in the absence of air.