General Principles and Processes of Isolation of Elements Class 12 MCQs Questions with Answers

1. Common impurities present in bauxite are:

2. Electrolytic reduction of Al2O3 to Al by Hall- Herault process is carried out:

3. During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are:

4. The method of zone refining of metals is based on the principle of:

5. The method of zone refining of metals is based upon the principle of:

6. Which of the following ores is concentrated by chemical leaching method?

7. Sulphide ore of zinc/copper is concentrated by:

8. Which of the following oxides cannot be reduced by hydrogen?

9. The oil used as frothing agent in froth floatation process is:

10. Cassiterite is the ore of which metal?

11. Concentration of sulphide ore is done by:

12. In the equation,

4M + 8CN– + H2O + O2 → 4[M(CN)2]– + 4OH–, the metal M is

13. The significance of leaching in the extraction of aluminium is:

14. The purest form of iron is:

15. In a thermite process is used as reducing agent:

16. Bessemer converter is used in the manufacture of:

17. Heating ore with carbon in the absence of air is known as:

18. For which of the following ores froth floatation method is used for concentration?

19. Formula of copper pyrite is:

20. In metallurgical process, aluminium acts as: