MCQs of General Principles and Processes of Isolation of Elements

General Principles and Processes of Isolation of Elements MCQs

MCQs of General Principles and Processes of Isolation of Elements

Showing 71 to 80 out of 154 Questions

71.

Which of the following substances is added as froth stabilizer in froth floatation method ?

(a)	Cresol
(b)	Toluene
(c)	Aniline
(d)	Both (A) and (C)

72.

The function of reducing substance is _____ .

(a)	to make the value of ΔGº to be positive
(b)	to make the value of ΔGº to be negative
(c)	to make the value of ΔGº to be zero
(d)	to keep the ΔGº to be constant

73.

In electrolysis of molten solids, if melting point of solid is very high, some substances are added to bring melting point down. What is this substance called ?

(a)	Reduction
(b)	Calcination
(c)	Flux
(d)	Coagulant

74.

Which substance is used as adsorbent in chromatographic method ?

(a)	Al₂O₃
(b)	SiO₂
(c)	MgO
(d)	All of the above

75.

In how many steps is the dry metallurgical method used for extraction of copper metal ?

(a)	2
(b)	3
(c)	4
(d)	5

76.

In Bessemerization, which metals are present in trace proportions along with copper obtained ?

(a)	Zn, Si, As, Bi, Au, Pt, Sb
(b)	Zn, Mg, Ag, Bi, Pt, As
(c)	Au, Zn, Si, Ag, Bi, Mg, C
(d)	Zn, Si, Pt, P, Sb, C, Au

77.

Which is the furnace used in extraction of iron metal ?

(a)	Reverberatory furnace
(b)	Open furnace
(c)	Blast furnace
(d)	Furnace

78.

What is the name of method used for refining of aluminium ?

(a)	van Arkel
(b)	Bessemerization
(c)	Hall-Heroult
(d)	Heitler-London

79.

What is the principle involved in chromatographic separation ?

(a)	Precipitation
(b)	Hydration
(c)	Decomposition
(d)	Adsorption

80.

Match the details of Part-I with those of Part-II by selecting proper correct options from Part-II.

Part-I	Part-II
(1) Prediction by the values of ΔGº and Eº for the following reaction: Cu²⁺_(aq)+ Fe_(s) → Fe²⁺_(aq) + Cu_(s)	(a) The reaction will occur spontaneously when ΔGº is positive and Eº < 0.
(2) Use of cryolite to get Al from Al₂O₃	(b) The reaction will occur spontaneously for ΔGº < 0 and Eº > 0.
(3) What is the cathode to get pure metal ?	(c) Cryolite acts as a flux.
(4) To which reaction does ΔGº = -nFEº > 0 apply ?	(d) Due to presence of cryolite, reduction of Al³⁺ becomes easy.
	(e) Electrode of highly pure metal.
	(f) Electrode made of impure metal.
	(g) 2Al_(s) + Cu²⁺_(aq) →3Cu_(s) + 2Al³⁺_(aq)
	(h) Fe²⁺_(aq) + Cu_(s)→ Cu²⁺_(aq)+ Fe_(s)

(a)	(1) → (b), (2) → (d), (3) → (f), (4) → (g)
(b)	(1) → (b), (2) → (d), (3) → (e), (4) → (h)
(c)	(1) → (a), (2) → (c), (3) → (f), (4) → (h)
(d)	(1) → (b), (2) → (c), (3) → (e), (4) → (g)

Showing 71 to 80 out of 154 Questions