General Principles and Processes of Isolation of Elements  MCQs

MCQs of General Principles and Processes of Isolation of Elements

Showing 41 to 50 out of 154 Questions
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41.
State the formula of fluorspar useful in Hall-Heroult method ?
(a) Na3AlF6
(b) CaCl2
(c) CaF2
(d) SiF4
Answer:

Option (c)

42.
Which of the following acts as a reducing agent in Hall-Heroult process ?
(a) Na3AlF6
(b) CaF2
(c) Graphite
(d) Al2O3
Answer:

Option (c)

43.
How does aluminium act in thermite process to get metals from the oxides of chromium and manganese ?
(a) Oxidizing agent
(b) Reducing agent
(c) Flux
(d) Soldering agent
Answer:

Option (b)

44.
The ore of copper containing carbonate or oxide is heated in _____ with a suitable reducing agency agent.
(a) blast furnace
(b) reverberatory furnace
(c) fire furnace
(d) bessemer's converter
Answer:

Option (d)

45.
Which of the following steps does not fit (does not appear) in dry metallurgical process ?
(a) Concentration
(b) Roasting
(c) Smelting
(d) Liquation
Answer:

Option (d)

46.
State the purity percentage of blister copper.
(a) 99%
(b) 88%
(c) 99.5%
(d) 95%
Answer:

Option (d)

47.
In thermal refining, silicates of which metals float as slag on copper ?
(a) Ag, Au and Pt
(b) Fe, Bi and Zn
(c) Si, As and Bi
(d) Sb, Bi and Pt
Answer:

Option (b)

48.
Which method of refining is employed to get 99.96 to 99.99% pure copper ?
(a) Thermal refining
(b) Electrolysis
(c) Reduction
(d) Vapour phase refining
Answer:

Option (b)

49.
The chemical composition of the slag formed during the smelting process in the extraction of copper is _____ .
(a) FeSiO3
(b) CuFeS2
(c) Cu2S + FeO
(d) Cu2O + FeS
Answer:

Option (a)

50.
Why does copper become brittle during thermal purification of copper ?
(a) Cu2S produced during the process dissolves in copper
(b) FeO produced during the process dissolves in copper
(c) CuO produced during the process dissolves in copper
(d) Cu2O produced during the process dissolves in copper
Answer:

Option (d)

Showing 41 to 50 out of 154 Questions
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