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

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

2. In the equation,

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

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

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

5. Common impurities present in bauxite are:

6. Cassiterite is the ore of which metal?

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

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

9. Formula of copper pyrite is:

10. In metallurgical process, aluminium acts as:

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

12. Concentration of sulphide ore is done by:

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

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

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

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

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

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

19. Bessemer converter is used in the manufacture of:

20. The purest form of iron is: