General Princip...

Fill in the blanks with the correct choice.
The undesired impurities present in the ores are called ___(i)___. To remove the volatile impurities from the ore, the ___(ii)___ process is carried out. Flux combines with non-fusible impurities to form ___(iii)___. $$CaO$$ acts as a ___(iv)___ flux.

Ellingham diagram represents change of:

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

Which of the following statements is correct?
(i) Copper is extracted by hydrometallurgy from low-grade ores.
(ii) In the electrolytic reduction of alumina, graphite is acting as an anode and steel vessel with the lining of carbon acts as an anode.
(iii) In Hall-Heroult process, aluminium is obtained at anode and CO and $$CO_2$$ are produced at the cathode.

Which of the following is used as a method of purification for silicon?

Four metals and their methods of refinement are given
(i) $$Ni,\ Cu,\ Zr,\  Ga$$
(ii) Electrolysis, van Arkel process, zone refining, Mond's process
Choose the right method for each:

Which of the following is not a method of refining of metals?

In this method, a low melting metal like tin can be made to flow on a sloping surface. In this way it is separated from higher melting impurities. The method is known as:

A number of elements are available in earth's crust but most abundant elements are _______.

Extraction of chlorine from brine is based on: