Question

What is the principle behind the method used for the refining of nickel?

Answer 1

a) Refining of nickle :- Mond's process : Impure nickle on reaction with carbon monoxide forms tetracarbonyl nickle which decomposes to form pure nickle and carbon monoxide.

Ni+4CO330−350k−→−−−−−−−Ni(CO)4Ni+4CO330−350k→Ni(CO)4

Ni(CO)4450−470k−→−−−−−−−Ni+4CONi(CO)4450−470k→Ni+4CO

(b) Refining of zirconium : Van- Arkel Method :

Impure metal Zr is heated with I2I2 to get zrI4zrI4 which is heated strongly at 2075K2075K to get zrzr

Zr+2I2870k−→−−ZrI4Zr+2I2870k→ZrI4

ZrI42075k−→−−−zr+2I2ZrI42075k→zr+2I2

(c) Purification of Tin : liquidation :- Impure metal is heated is at the top of sloping furnace so that tin melts but impurity does not .

So that tin melts but impurity does not .

Molten tin flows down and pure tin so formed is collected.