(i) Both assertion and reason are true and the reason is the correct explanation of assertion. (ii) Both assertion and reason are true but the reason is not the correct explanation of assertion....
(i) Both assertion and reason are true and the reason is the correct explanation of assertion. (ii) Both assertion and reason are true but the reason is not the correct explanation of assertion....
(i) Both assertion and reason are true and the reason is the correct explanation of assertion. (ii) Both assertion and reason are true but the reason is not the correct explanation of assertion....
(i) Both assertion and reason are true and the reason is the correct explanation of assertion. (ii) Both assertion and reason are true but the reason is not the correct explanation of assertion....
(i) Both assertion and reason are true and the reason is the correct explanation of assertion. (ii) Both assertion and reason are true but the reason is not the correct explanation of assertion....
Column I Column II (A) Pendulum (1) Chrome steel (B) Malachite (2) Nickel steel (C) Calamine (3) Na3AlF6 (D) Cryolite (4) CuCO3.Cu(OH)2 (5) ZnCO3 Column I Column II (A) Pendulum (2)...
Column I Column II (A) Coloured band (1) Zone refining (B) Impure metal to volatile complex (2) Fractional distillation (C) Purification of Ge and Si (3) Mond Process (D) Purification of mercury (4)...
Column I Column II (A) Cyanide process (1) Ultrapure Ge (B) Froth Floatation Process (2) Dressing of ZnS (C) Electrolytic reduction (3) Extraction of Al (D) Zone refining (4) Extraction of Au ...
Column I Column II (A) Sapphire (1) Al2O3 (B) Sphalerite (2) NaCN (C) Depressant (3) Co (D) Corundum (4) ZnS (5) Fe2O3 Column I Column II (A) Sapphire (3) Co (B) Sphalerite (4) ZnS (C)...
Column I Column II (A) Blistered Cu (1) Aluminium (B) Blast furnace (2) 2Cu2O + Cu2S → 6Cu + SO2 (C) Reverberatory furnace (3) Iron (D) Hall-Heroult process (4) FeO + SiO2 → FeSiO3 (5) 2Cu2S...
Reactions Involved: 4Au(s) + 8CN-(aq) + 2H2O(aq) + O2(g) → 4[Au(CN)2]-(aq) + 4OH-(aq) 2[Au(CN)2]-(aq) + Zn(s) → 2Au(s) + [Zn(CN)4]2- (aq) Role of Zinc in this reaction - Reducing...
Requirements for vapour phase refining: 1. Metal must react easily with a reagent to produce volatile complex. 2. The complex which is volatile should be easily decomposed and recovered.
Reactions Involved: 1. 3Fe2O3 + CO → 2Fe3O4 + CO2 2. Fe3O4 + CO → 3FeO + 2CO2 3. Fe2O3 + CO → 2FeO + CO2
1. Semiconductors are purified by the method of zone refining. 2. The refining of the surface depends on the principle that the impurities are more soluble in molten metal than solid metal. 3. The...
Role of flux in metallurgical processes: 1. To remove the gangue, certain substances are mixed with it. These are called fluxes. 2. Flux can be basic or acidic. 3. Flux which is acidic removes basic...
Considerations during the extraction of metals by electrochemical method: 1. The reactivity of the formed metal. 2. Electrodes must be made of suitable materials 3. To form a molten mass, flux is...
Reaction involved in the extraction of Cl2 from brine: 2Cl- (aq) + 2H2O(l) → 2OH- (aq) + H2(g) + Cl2(g) Calculation: ΔGᶱ = -nFE° ΔGᶱ = +422kJmol-1. E° = 422x103 / 2×96500 E° = - 2.2V For the...
The ∆G formation of FeO is a bit negative than the ∆G formation of carbon monoxide from carbon. Summation of both ∆G will be negative at about 1073K. Above 1073K the FeO production line exceeds the...
Limestone can be combined with flux to remove impurities of sulfur, silicon and phosphorus. They form an easily removable slag. The metal is removed from the slag by passing through the rollers....
Copper is extracted by hydrometallurgy method from the copper ores which are low graded. The Cu is treated with cast iron or H2 and is leached out by the acid. Reaction Involved: Cu2 (aq) + H2(g) →...
1. The metal must react easily with a reagent to produce complex. 2. The complex which is volatile must be easily decomposed and do not give off any additional products and recovery must also be...
Carbon and hydrogen will not reduce oxides into metals but will instead build hydrides and carbides. Thus, they are not used as the reducing agents.
The two sulphide ores competing with coming into the froth can be separated by adjusting the oil to the amount of water or by adding depressants such as NaCN. If we have two sulphide metals, ZnS and...
The iron ore which is used to line the reverberatory furnace is Haematite ore (Fe2O3). Example: In the following reaction, Haematite ore forms iron and CO. Fe2O3 + 3 C → 2 Fe + 3CO
Compound A does not absorb well in the column and moves down the column with alcohol i.e. eluant, while compound B is well absorbed in the column and cannot go down the column.
The copper sulphide ore is burned in the furnace after mixing with silica because the metal impurities present in it can form slag and silica and will be easily removed. Copper is produced as matte...
The Sulphide ores cannot be easily reduced so they are usually converted to oxides because the oxides can be easily reduced.
The Van Arkel method is used to filter Zr and Ti. Van Arkel's process involves heating the impure metal with Iodine. It builds a complex structure where it decomposes at high temperatures, restores...
(i) Cl–(aq.) →1/2Cl2 (g) + e– ; E°cell = 1.36V (ii) 2H2O(l) → O2(g0 + 4H+ + 4e- ; E°cell = 1.23V (iii) Na+(aq) + e- → Na(s) ; E°cell = 2.71V (iv) H+(aq) + e- → 1/2H2(g) ; E°cell = 0.00V ...
(i) Al3+ is oxidised to Al (s). (ii) graphite anode is oxidised to carbon monoxide and carbon dioxide. (iii) the oxidation state of oxygen changes in the reaction at the anode. (iv) the oxidation...
(i) Cu and Zn (ii) Ge and Si (iii) Zr and Ti (iv) Zn and Hg Correct Answer: (i) Cu and Zn Explanation: Electrolytic refining is used to purify Copper and Zinc metals.
(i) displacement of metal by some other metal from the complex ion. (ii) roasting of the metal complex. (iii) calcination followed by roasting. (iv) thermal decomposition of the metal complex....
(i) Below temperature at point A. (ii) Approximately at the temperature corresponding to point A. (iii) Above temperature at point A but below a temperature at point D. (iv) Above temperature at...
(i) be reduced by carbon monoxide only. (ii) be reduced by both carbon monoxide and carbon. (iii) be reduced by carbon only. (iv) not be reduced by both carbon and carbon monoxide. Correct...
(i) ∆G value for the overall reduction reaction with carbon monoxide is zero. (ii) ∆G value for the overall reduction reaction with a mixture of 1 mol carbon and 1 mol oxygen is positive. (iii) ∆G...
(a) C + O2 → CO2 (b) 2C + O2 → 2CO (c) 2CO + O2 → 2 CO2 (i) Point A (ii) Point B (iii) Point D (iv) Point E Correct Answers: (ii) Point B (iv) Point E Explanation: At the temperature...
(i) Cast iron is obtained by remelting pig iron with scrap iron and coke using hot air blast. (ii) In the extraction of silver, silver is extracted as cationic complex. (iii) Nickel is purified by...
(i) lower the melting point of Al2O3 (ii) increase the conductivity of molten mixture. (iii) reduce Al3+ into Al(s). (iv) acts as a catalyst Correct Answers: (i) lower the melting point of...
(i) Collectors enhance the non-wettability of the mineral particles. (ii) Collectors enhance the wettability of gangue particles. (iii) By using depressants in the process two sulphide ores can be...
(i) using collectors. (ii) adjusting the proportion of oil to water. (iii) using depressant. (iv) using froth stabilisers. Correct Answers: (ii) adjusting the proportion of oil to water....
(i) CuO (ii) ZnO (iii) Fe2O3 (iv) SiO2 Correct Answers: (iii) Fe2O3 (iv) SiO2 Explanation: Common impurities present in bauxite are Fe2O3 and SiO2
(i) Haematite (ii) Galena (iii) Copper pyrites (iv) Magnetite Correct Answers: (ii) Galena (iii) Copper pyrites Explanation: Galena and Copper pyrites are the ores which can be concentrated...
(i) CaCO3→CaO+CO2 (ii) 4FeS2+11O2→2Fe2O3+8SO2 (iii) 2Al(OH)3→Al2O3+3H2O (iv) Cu2S+2CuO→4Cu+SO2 Correct Answers: (i) CaCO3→CaO+CO2 (iii) 2Al(OH)3→Al2O3+3H2O Explanation:...
(i) haematite (ii) calamine (iii) iron pyrites (iv) sphalerite Correct Answers: (i) haematite (ii) calamine Explanation: Haematite and Calamine are the calcined ores which gets reduced by...
(i) Fe2O3 + 3CO → 2Fe + 3CO2 (ii) FeO + SiO2 → FeSiO3 (iii) Fe2O3 + 3C → 2Fe + 3CO (iv) CaO + SiO2 → CaSiO3 Correct Answers: (i) Fe2O3 + 3CO → 2Fe + 3CO2 (iv) CaO + SiO2 → CaSiO3 Explanation:...
(i) heating with a stream of carbon monoxide. (ii) heating with iodine. (iii) liquation. (iv) distillation. Correct Answers: (i) heating with a stream of carbon monoxide (ii) heating with...
(i) A depressant prevents a certain type of particle to come to the froth. (ii) Copper matte contains Cu2S and ZnS. (iii) The solidified copper obtained from the reverberatory furnace has blistered...
(i) ΔG° for the overall reaction is negative. (ii) ΔG° for the overall reaction is positive. (iii) E° for the overall reaction has a negative value. (iv) E° for the overall reaction has a positive...
(i) oxidation of Cl– ion to chlorine gas occurs. (ii) reduction of Cl– ion to chlorine gas occurs. (iii) For the overall reaction, ∆Gᶱ has a negative value. (iv) a displacement reaction takes place....
(i) sulphides of copper (II) and iron (II) (ii) sulphides of copper (II) and iron (III) (iii) sulphides of copper (I) and iron (II) (iv) sulphides of copper (I) and iron (III) Correct...
(i) Fe3O4 + 4CO → 3Fe + 4CO2 (ii) Cu2O + C → 2Cu + CO (iii) Cu2+ (aq) + Fe (s) → Cu (s) + Fe2+ (aq) (iv) Cu2O + 1/2Cu2S → 3Cu + 1/2SO2 Correct Answer: (iv) Cu2O + 1/2Cu2S → 3Cu + 1/2SO2...
(i) Al and Fe (ii) Al and Cu (iii) Fe and Cu (iv) Cu and Ag Correct Answer:(i) Al and Fe Explanation: The most abundant elements in the earth's crust are Aluminium (8.1 %) and Iron...
(i) FeS (ii) CO (iii) Cu2S (iv) SO2 Correct Answer: (iii) Cu2S Explanation: Reaction Involved - 2Cu2S+3O2 →2Cu2O+2SO2 2 Cu2O+ Cu2S →6Cu+ SO2
(i) impurities of low boiling metals can be separated by distillation. (ii) impurities are more soluble in molten metal than in solid metal. (iii) different components of a mixture are differently...