METALLURGY PCQS METALLURGY METALLURGY PCQS OBJECTIVE QUESTIONS PCQs
METALLURGY PCQ’S METALLURGY
METALLURGY PCQ’S OBJECTIVE QUESTIONS (PCQs)
METALLURGY PCQ’S 1. In the context of the Hall-Heroults process for the entraction of Al. Which of the following statement is false [EAMCET-2015] Solution :
METALLURGY PCQ’S 2. The metal that cannot be obtained by electrolysis of an aqueous solution of its salts is: [JEEMAINS-2014] 1) Ag 2) Ca 3) Cu 4) Cr Solution : Except ‘Ca’ all elements are obtained by electrolysis.
METALLURGY PCQ’S 3. Which one of the following ores is known as Malachite : [J. M. O. L-2014] Solution : Malachite Cu(OH)2. Cu. CO 3
METALLURGY PCQ’S 4. Which series of reactions correctly represents chemical reactions related to iron and its compounds? [JEE-2014]
METALLURGY PCQ’S Solution : KEY : 2
METALLURGY 5. Calcination is the process in which : PCQ’S (JEE MAINS ONLINE-2013) 1) Ore is heated strongly below its melting point either in the limited or absence of air and is used to convert carbonates and hydrated oxide ores of their respective oxides 2) Ore is heated strongly below its melting point in the presence of excess of air and is used for the conversion of carbonates and hydrated oxide ores to their respective oxides.
METALLURGY PCQ’S 3) Ore is heated strongly above its melting point in the limited supply of air to convert sulphide ores to their respective oxides. 4) Ore is heated strongly below its melting point in the absence or limited supply of air and is used for the conversion of sulphide ores to their respective oxides. Solution : Calcination is the process of heating the ore in absence of air below its melting point to give softened ore with loss of volatile impurities and decomposition of carbonates and dehydration of hydrated ores
METALLURGY PCQ’S 6. In Goldschmidt alumino thermic process which of the following reducing agents is used: (JEE MAINS ONLINE-2013) 1) coke 2) calcium 3) sodium 4) Al-powder Solution : 2 Al + Fe 2 O 3 Al 2 O 3 + 2 Fe + 200 Kcal
METALLURGY PCQ’S 7. Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly ? [A-2008] 1) Metal sulphides are thermodynamically more stable than CS 2 2) CO 2 is thermodynamically more stable than CS 2 3) Metal sulphides are less stable than the corresponding oxides 4) CO 2 is mroe volatile than CS 2 Solution : Metal sulphides are converted to metal Oxides
METALLURGY PCQ’S 8. Which of the following oxides is amphoteric in nature 1) Sn. O 2 2) CO 2 3) Si. O 2 4) Ca. O Solution : [A- 2005]
METALLURGY PCQ’S 9. Heating mixture of Cu 2 O and Cu 2 S will give 4) Cu 2 S Solution : [A-2005]
METALLURGY 1) Hg – NH 2 – Cl 2) NH 2 – Hg – Cl 3) Hg 2 O 4) Hg. O Solution : PCQ’S [A- 2005]
METALLURGY PCQ’S 11. Which one of the following ores is best concentrated by froth-flotation method? [A-2004] 1) Galena 2) Cassiterite 3) Magnetite 4) Malachite Solution : Galena (Pb. S)
METALLURGY PCQ’S 12. The substance not likely to contain Ca. CO 3 is 1) Calcined gypsum 2) Sea shells 3) Dolomite 4) A marble statue Solution : [A-2003]
METALLURGY PCQ’S 13. The metal extracted by leaching with a cyanide is 1) Mg 2) Ag 3) Cu 4) Na Solution : By leaching process Ag is extracted. [A- 2002]
METALLURGY PCQ’S 14. Cyanide process is used for the extraction of 1) Ba 2) Al 3) B 4) Ag Solution : By leaching process Ag is extracted. [A-2002]
METALLURGY PCQ’S 15. When the sample of copper with zinc impurity is to be purified by electrolysis, the appropriate electrodes are [A- 2002] Cathode 1) pure zinc Anode pure copper 2) pure copper impure sample 3) impure zinc 4) pure copper pure sample Solution : In electrolysis process Cathode is pure copper Anode is impure sample
METALLURGY PCQ’S 16. Extraction of zinc from zinc blende is achieved by 1) Roasting followed by self reduction 2) Electrolytic reduction 3) Roasting followed by reduction with another metal 4) Roasting followed by reduction with carbon Solution : Roasting Process
METALLURGY PCQ’S 17. Which of the oxide groups among the following cannot be reduced by carbon ? 1) Ca. O, K 2 O 2) Cu 2 O, Sn. O 2 3) Fe 2 O 3, Zn. O 4) Pb. O, Fe. O 4 Solution :
METALLURGY PCQ’S 18. In the electrolysis of alumina to obtain aluminum metal, cryolite is added mainly to: 1) lower the melting point of alumina 2) dissolve alumina in molten cryolite 3) increase the electrical conductivity 4) remove the impurities of alumina
METALLURGY PCQ’S 19. The substance used as froth stabilizers in froth –floatation process is 1) Potassium ethyl xanthate 2) Sodium cyanide 3) Copper sulphate 4) Aniline
METALLURGY PCQ’S 20. Which one of the following ores is best concentrated by froth-flotation method? 1) Magnetite 2) Siderite 3) Galena 4) Malachite Solution : Galena (Pb. S) [A-2004]
METALLURGY PCQ’S 21. Extraction of copper by smelting uses silica as an additive to remove 1) Cu 2 O 2) Fe. S 3) Fe. O 4) Cu 2 S Solution : Fe. O is gangue and Si. O 2 is flux to form slag Fe. Si. O 3 Fe. O + Si. O 2 Fe. Si. O 3
METALLURGY PCQ’S (PCQs) EAMCET
METALLURGY PCQ’S 1. Which of the following process does not involve heating [AP EAMCET-2015] 1) Calcination 2) Smelting 3) Roasting 4) Levigation Solution : Except levigation remaining involves heating
METALLURGY PCQ’S 2. German silver contains which of the following metals? [TS EAMCET-2015] 1) Cu, Zn 2) Fe, Zn 3) Zn, Fe, Ni 4) Cu, Zn, Ni Solution : German Silver = Cu, Zn, Ni
METALLURGY PCQ’S 3. Which of the following is used for the extraction of Zn [EAMCET-2015] 1) Bauxite 2) Magnetite 3) Malachite 4) Sphalerite Solution : Sphalerite- Zn. S
METALLURGY PCQ’S 4. What is the role of limestone during the extraction of iron from haematite ore ? [E-2014] 1) Oxidizing agent 2) Reducing agent 3) Flux 4) Leaching agent Solution : Basic flux
METALLURGY PCQ’S 5. Which one of the following method is used in the concentration of sulphide ore [E-2014] 1) froth floatation 2) smelting 3) roasting 4) leaching
METALLURGY PCQ’S 6. During the manufacture of cast iron, the slag (Ca. Si. O 3) is formed in 1) Zone of reduction only [E-2013] 2) Zone of fusion only 3) Zone of reduction and zone of fusion 4) Zone of heat absorption Solution :
METALLURGY PCQ’S 7. Which of the following is not added during the extraction of silver by cyanide process. [E-2013] 1) Na. CN 2) Air 3) Zn 4) Na 2 S 2 O 3 Solution :
METALLURGY PCQ’S 8. In the electrolysis of alumina using cryolite, the reaction that takes place at cathode is. [E-MED-2012] 1) 4 H 2 O + 4 e- 2 H 2+ 4 OH 2) 4 Al+3 + 12 e- 4 Al 3) 6 F 2 + 2 Al 2 O 3 4 Al. F 3 + 3 O 2 4) 12 F- 6 F 2 + 12 e-
METALLURGY PCQ’S 9. Which of the following metallurgical process does not involve heating? [EAMCET-2011] 1) Roasting 2) Levigation 4) Calcination Solution : In Levigation heating is not involved
METALLURGY PCQ’S 10. Which one of the following is the mineral for tin? 1) Galena 2) Cerussite 3) Cassiterite 4) Anglesite Solution : [E-2010]
METALLURGY PCQ’S 11. The process used in the refining of Al & Zn metals are respectively 1) hoope’s process and fractional distillation [E-2010] 2) hoope’s process and cupellation 3) polling and fractional distillation 4) cupellation and fractional distillation
METALLURGY 12. Match the following List-I A) Feldspar B) Asbestos C) Pyrargyrite D) Diaspore List-II I) [Ag 3 Sb. S 3] II) Al 2 O 3. H 2 O III) Mg. SO 4. H 2 O IV) KAl. Si 3 O 8 V) Ca. Mg 3(Si. O 3)4 The correct answer is A B C D 1) IV V II I 2) IV V I II 3) IV I II 4) II V IV I PCQ’S [E-2009]
METALLURGY PCQ’S 13. The chemical formula of feldspar is 1) KAl. Si 3 O 8 2) Na 3 Al. F 6 3) Na. Al. O 2 4) K 2 SO 4. Al 2(SO 4)3. 4 Al(OH)3 Solution : Chemical formula of feldspar is KAl. Si 3 O 8 [E-2007]
METALLURGY PCQ’S 14. Observe the following statements regarding purification of bauxite: I. During Hall's process, silica is removed as Si (Vapour). [E-2005] II. Bauxite ore contaminated with Fe 2 O 3 is purified in Baeyer's process. III. During Serpeck's process, Al. N is formed. The correct answer is 1) I, II, and III are correct 2) Only II, III are correct 3) Only I, III are correct 4) Only II, IV are correct Solution : Concepts of Baeyer’s, Serpeck’s processes
METALLURGY PCQ’S 15. Which one of the following is used as an acid flux in metallurgy ? [E-2004] 1) Ca. O 2) Si. O 2 3) Na 2 CO 3 4) SO 2 Solution :
METALLURGY PCQ’S 16. During the electrolysis of cryolite, aluminium and fluorine are formed in. . . molar ratio: [E-2003] 1) 1: 2 2) 2: 3 3) 1: 1 4) 1: 3
METALLURGY PCQ’S Solution : 4 Al. F 3 4 Al+3 + 12 F- At cathode: 4 Al+3 + 12 e. At anode: 12 F- Al : F 4: 6 2: 3 4 Al 6 F 2 + 12 ekey : 2
METALLURGY PCQ’S 17. Which of the following is a sulphide ore? 1) Calamine 2) Cryolite 3) Zinc Blende 4) Haematite Solution : Zinc Blende (Zn. S) [E-2002]
METALLURGY PCQ’S Thank you…
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