Which of the following set of elements mostly occur as sulphide ores.

Options

A. Zn, Cu,Na
B. Zn, Cu, Pb
C. Fe, Al, Ti
D. Cu, Ag, Au

Answer

To determine which set of elements mostly occurs as sulphide ores, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Elements in Each Option**:
- Option A: Zinc (Zn), Copper (Cu), Sodium (Na)
- Option B: Zinc (Zn), Copper (Cu), Lead (Pb)
- Option C: Iron (Fe), Copper (Cu), Zinc (Zn)
- Option D: Gold (Au), Silver (Ag), Copper (Cu)

2. **Analyze Option A**:
- Zinc (Zn) is found in sulphide ore (ZnS).
- Copper (Cu) is also found in sulphide ore (Cu2S).
- Sodium (Na) is not found in sulphide ores; it is typically found as NaCl (table salt).
- **Conclusion**: Option A is not the answer.

3. **Analyze Option B**:
- Zinc (Zn) is found in sulphide ore (ZnS).
- Copper (Cu) is found in sulphide ore (Cu2S).
- Lead (Pb) is found in sulphide ore (PbS).
- **Conclusion**: All elements in Option B are found in sulphide ores. This option is a strong candidate.

4. **Analyze Option C**:
- Iron (Fe) is primarily found in oxide ores (e.g., Fe2O3) and not as a sulphide.
- Copper (Cu) is found in sulphide ore (Cu2S).
- Zinc (Zn) is found in sulphide ore (ZnS).
- **Conclusion**: Since Iron is not found in sulphide ores, Option C is not the answer.

5. **Analyze Option D**:
- Gold (Au) is typically found in its native form and not as a sulphide.
- Silver (Ag) can occur in various forms, but it is not primarily a sulphide.
- Copper (Cu) is found in sulphide ore (Cu2S).
- **Conclusion**: Since Gold is not found in sulphide ores, Option D is not the answer.

6. **Final Conclusion**:
- The only option where all elements are primarily found as sulphide ores is **Option B** (Zinc, Copper, Lead).

### Answer:
The correct answer is **Option B: Zinc (Zn), Copper (Cu), Lead (Pb)**.

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