Class 12 Chemistry Chapter 6 General Principles and Processes of Isolation of Elements MCQs | Class 12 Chemistry Chapter 6 General Principles and Processes of Isolation of Elements Multiple Choice Questions (MCQs) and Answers

Sports GK Questions and Answers 2024 (Latest Updated)

Awards & Honours GK Questions 2024 (Latest Updated)

Questions
1 In electrorefining of copper some gold is produced as:
A cathode mud
B anode mud
C cathode deposit
D None of these

Answer:anode mud
2 In the electrolytic method of obtaining aluminium from purified bauxite, cryolite is added to the charge in order to:
A lower the melting point of bauxite
B dissolve bauxite and render it a conductor of electricity
C protect aluminium produced from oxygen
D minimise the heat loss due to radiation

Answer:dissolve bauxite and render it a conductor of electricity
3 The purest form of iron is:
A cast iron
B pig iron
C wrought iron
D steel

Answer: wrought iron
4 During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are:
A Pb and Zn
B Sn and Ag
C Fe and Ni
D Ag and Au

Answer:Ag and Au
5 Extraction of zinc from zinc blende is achieved by
A electrolytic reduction
B roasting followed by reduction with carbon
C roasting followed by reduction with another metal
D roasting followed by self-reduction

Answer: roasting followed by reduction with carbon
6 In the equation
4M + 8CN– + H2O + O2 → 4[M(CN)2]– + 4OH–, the metal M is
A copper
B iron
C gold
D Zinc

Answer:gold
7 Heating ore with carbon in the absence of air is known as:
A reduction
B carbon-reduction
C smelting
D Roasting

Answer:smelting
8 In the extraction of copper from sulphide ore, the metal is formed by reduction of Cu2O with
A FeS
B CO
C Cu2S
D SO2

Answer:Cu2S
9 The method of zone refining of metals is based upon the principle of
A greater solubility of the impurity in molten state than in solid
B greater mobility of pure metal than impurity
C higher melting point of impurity than that of pure metal
D greater noble character of solid metal than that of the impurity

Answer:greater solubility of the impurity in molten state than in solid
10 Classiterite is the ore of which metal?
A Mn
B Sb
C Sn
D Ni

Answer:Sn
11 The electrolytic reduction technique is used in the extraction of
A Highly electronegative elements
B Highly electropostive elements
C Metalloids
D Transition metals

Answer:Highly electropostive elements
12 In the commercial electrochemical process for aluminium extraction, electrolyte used is
A Al(OH)3 is NaOH solution
B An aqueous solution of Al2 (SO4)3
C A molten mixture of Al2O3 and Na3AlF6
D A molten mixture of Al2O3 and Al(OH)3

Answer: A molten mixture of Al2O3 and Na3AlF6
13 Electrolytic reduction of Al2O3 to Al by Hall- Herault process is carried out
A in presence of NaCl
B in presence of fluorite
C in presence of cryolite which forms a melt with lower melting point
D in presence of cryolite which forms a melt with high melting point

Answer:in presence of cryolite which forms a melt with lower melting point
14 The chemical composition of ‘slag’ formed during the melting process in the extraction of copper is
A Cu2O + FeS
B FeSiO3
C CuFeS2
D Cu2S + FeO

Answer: FeSiO3
15 Bessemer converter is used in the manufacture of
A Pig iron
B Steel
C Wrought iron
D Cast iron

Answer:Steel
16 The method of zone refining of metals is based on the principle of
A greater mobility of the pure metal than that of the impurity
B higher melting point of the impurity than that of the pure metal
C greater noble character of the solid metal than that of impurity
D greater solubility of the impurity in the molten state than in the solid

Answer: greater solubility of the impurity in the molten state than in the solid
17 In the leaching of Ag2S with NaCN, a stream of air is also passed. It is because
A The reaction between Ag2S and NaCN is reversible.
B to oxidise Na2S formed in the reaction to Na2SO4
C to oxidise Ag2S to Ag2O
D Both (a) and (b)

Answer: Exothermic
18 Purest form of iron is
A Cast iron
B Hard Steel
C Stainless steel
D Wrought iron

Answer:Wrought iron
19 Concentration of sulphide ore is done by
A froth flotation process
B electrolysis
C roasting
D None of these

Answer: froth flotation process
20 Malachite is an ore of
A iron
B copper
C zinc
D Sliver

Answer: copper
Assam Direct Recruitment Test Series

Teacher Eligibility Test

Assam Direct Recruitment Test Series