Leaching

Q.

How are impurities removed from bauxite?

Q. In the extraction of copper from copper pyrites, iron is removed as:

1. $FeS{O}_4$
2. $FeSi{O}_3$
3. $Fe3O_4$
4. $F{e}_2{O}_3$

Q.

Which of the following is not suitable for leaching?

1. Gold

2. Silver

3. Bauxite

4. Magnesium

Q.

Which of the following processes is not a physical process of separation?

1. Levigation

2. Magnetic separation

3. Leaching

4. Froth floatation

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.

Which one of the following methods is best suited for the concentration of Bauxite ore?

1. Hydraulic washing

2. Hydrometallurgy

3. Magnetic separation

4. Leaching

Q. What is the nature of $N{a}_{2}O$ ? What happens when it is dissolve in water ? Write equation.