Metallurgy Flashcards
In Goldschmidt alumino thermic process, which reducing agents is used?
In Goldschmidt alumino thermic process Aluminium is used as the reducing agent.
The metal extracted by leaching with cyanide is
Silver is extracted by leaching with cyanide.
Ag2S + 2NaCN → Na[Ag(CN)2]
2Na[Ag(CN)2] + Zn → Na2[Zn(CN)4] + 2Ag
Aluminium is extracted by the electrolysis of
Alumina is mixed with cryolite in the extraction of aluminium metal.
Cyanide process is used for the extraction of
Cyanide process is used for the extraction of silver. Cyanide forms a soluble complex with silver. Ag is precipitated using zinc.
The smog is essentially caused by the presence of
Smog is smoke + fog. It is caused by a mixture of smoke and sulphur dioxide.
Which of the oxide groups cannot be reduced by carbon?
Highly reactive metals like K and Ca cannot be reduced by carbon. The oxides of less electropositive metals like Fe, Zn, Pb, Sn, Cu etc. are reduced by strongly heating them with coal or coke, in the blast furnace.
The ore that contains both iron and copper is
Copper pyrite is CuFeS2.
The Mond process is used for the
The Mond process is used for the extraction and purification of Ni.
Calamine is an ore of
Calamine (ZnCO3) is an ore of zinc.
Which ores are best concentrated by froth-flotation method?
Froth-floatation method is used for the concentration of sulphide ores.
With respect to ore, Ellingham diagram helps to predict the feasibility of its
Ellingham diagrams helps to predict the feasibility of thermal reduction of an ore.
The substance used as froth-stabilisers in froth-flotation process is:
Aniline is used to stabilise the froth.
The refining method used when the metal and the impurities have low and high melting temperatures, respectively, is :
Metal with low melting point containing impurities of high melting point can be purified by liquation
