JEE Main 2023 · 10 April · morning · Single correct · +4 / −1
Which of the following is used as a stabilizer during the concentration of sulphide ores?
- (a) Cresols
- (b) Xanthates
- (c) Fatty acids
- (d) Pine oils
Answer and solution
Answer (a) Cresols
Solution
Chemistry ma’am · 3 steps
In froth flotation, sort each reagent by its job: collector or froth stabiliser. Only one stabilises.
- The method. Sulphide ores are concentrated by froth flotation. Powdered ore is mixed with water and oil, and air is blown through. The sulphide particles stick to the oil froth and rise, while the gangue gets wet and sinks.
- Two kinds of reagent. Collectors make the ore particles water-repelling so they cling to the froth. Froth stabilisers keep the bubbles from collapsing so the froth lasts long enough to be skimmed off.
Reagent Role in froth flotation Cresols froth stabiliser Xanthates collector Fatty acids collector Pine oils collector - So. Cresols (along with aniline) act as froth stabilisers, so the answer is (a).
The idea to keep. Froth flotation pairs to remember: collectors are pine oils, fatty acids and xanthates; stabilisers are cresols and aniline. A depressant like NaCN separates one sulphide from another.
Answer from the NTA final answer key. Solution by PrepWiser.