Leaching

Q.

Which of the following statements are true for Leaching?

1. It involves treatment of ore with a suitable reagent as to make it soluble.

2. During leaching impurities remain insoluble and the ore is recovered from solution by using suitable chemical method.

3. Leaching offers excellent chemical selectivity and flexibility throughout the process and also minimizes the need for very high temperatures and refractory materials

4. All of the above

Q. Extraction of gold and silver involves leaching with $C{N}^{-}$ ion. Silver is later recovered by

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> NEET 2017

1. Zone refining
2. Liquation
3. Displacement with $Zn$
4. Distilation

Q. Which of the following process is not involved in the extraction of Fe?

1. Gravity separation
2. Leaching
3. Roasting
4. Carbon reduction

Q. Extraction gold and silver involves leaching with $C{N}^{-}$ ion. Silver is later recovered by:

1. Liquation
2. Distillation
3. Zone refining
4. Displacement with $Zn$