What type of ores are roasted?

Explanation

### Step-by-Step Solution:

1. **Understanding Roasting**: Roasting is a thermal process used primarily in metallurgy to convert ores into their respective oxides. It involves heating the ore in the presence of excess oxygen.

2. **Identifying the Type of Ores**: The ores that are typically roasted are **sulphide ores**. This is because sulphide ores need to be converted into oxides for further reduction to obtain metals.

3. **Chemical Reaction During Roasting**: When sulphide ores are roasted, they undergo a chemical reaction where they are heated with oxygen. For example, when a metal sulphide (e.g., ZnS for zinc) is roasted, it reacts with oxygen to form the corresponding metal oxide (ZnO) and sulfur dioxide (SO2) gas is released:
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