Elements used as semiconductors must be in highly pure form. Name the method used for purifying such metals and give the principle behind it.

Match the following:
       A                                                  B
1    Hydraulic washing              a    Tin
2    Bessemerisation                b    Aluminium
3    Hydrometallurgy                  c    Iron Pyrites
4    Hall Heroult  Process        d    Copper
5    Froth Floatation                   e    Silver
6    Liquation                               f    Magnetite

Identify the metal that can be purified by zone refining:
a) Si         b) Al         c)Ag             d)Cu 

Sulphide ores are generally concentrated by ------- process

Distinguish between calcination and roasting ?

Explain leaching.

Which of the following is the ore of zinc?

(a) Bauxite  b)Magnetite c)malachite d)calamine

a] Name the method used for removing gangue from sulphide ore?

b]Explain the above method.

Name the refining method of nickel?

Define a) Pig iron b) Cast iron c) Wrought iron

Although thermodynamically feasible in practise magnesium is not used for the reduction of alumina.why

Match the following

a) Zone refining - Sn

b) Van Arkel Method-Hg

c) Electrolytic refining- Ni

d) Mond's process- Cu

e) Distillation- Ti

f) Liquation- Ge

Explain zone refining with an example?

What is the role of limestone in the extraction of iron in blast furnace?

Which is the  purest form of iron?Give its preparation

The chemical method for concentration of ore is..................

What is Ellingham diagram ? Give its significance.

Outline the principle of refining of metals of the following method.

 (a)  Distillation

 (b)  Liquation

 (c) Electrolytic refining

 (d) Zone refining        

Match the following