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When roasting is carried out: (P) sulp...

When roasting is carried out:
(P) sulphde ore sare converted into oxide and suphate
(Q) Remove water of hydration
(R ) Melt the ore
(S) Remove arsenic and sulphur impurities

A

I, II & III are correct

B

I, III & IV are correct

C

I, II & IV are correct

D

II, III & IV are correct

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the processes that occur during roasting, we will analyze each statement (P, Q, R, S) and determine their validity based on the definition and characteristics of roasting. ### Step-by-Step Solution: 1. **Understanding Roasting**: Roasting is a metallurgical process used to extract metals from their ores. It involves heating the ore in the presence of oxygen, which leads to the conversion of sulfide ores into oxides and other compounds. 2. **Analyzing Statement P**: - **Statement P**: "Sulfide ores are converted into oxides and sulfates." - **Evaluation**: This statement is correct. During roasting, sulfide ores are oxidized, resulting in the formation of metal oxides and sometimes sulfates. 3. **Analyzing Statement Q**: - **Statement Q**: "Remove water of hydration." - **Evaluation**: This statement is also correct. Roasting can help in removing water of hydration from hydrated minerals, although this is not the primary purpose of roasting. 4. **Analyzing Statement R**: - **Statement R**: "Melt the ore." - **Evaluation**: This statement is incorrect. Roasting is performed below the melting point of the ore; it does not involve melting the ore. 5. **Analyzing Statement S**: - **Statement S**: "Remove arsenic and sulfur impurities." - **Evaluation**: This statement is correct. Roasting helps in removing impurities such as arsenic and sulfur by converting them into volatile oxides. 6. **Conclusion**: Based on the evaluations: - Statements P, Q, and S are correct. - Statement R is incorrect. Therefore, the correct statements when roasting is carried out are P, Q, and S. ### Final Answer: The correct options when roasting is carried out are P, Q, and S.
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