Description : Pig iron is manufactured from the ores by (A) Dressing (B) Calcination and roasting (C) Smelting (D) All the above
Last Answer : Answer: Option D
Description : Calcination of iron ores is done (A) To remove moisture (B) To remove carbonic acid (C) By roasting in heaps (D) All the above
Description : If the ore impurities is (A) Clay, lime stone is used as flux (B) Lime stone, clay is used as flux (C) Quartz, lime stone and argillaceous iron ores are used as flux (D) All the above
Description : Sulphur removal by heating of pyrite ore in presence of air is called its (A) Reduction (B) Roasting (C) Calcination (D) Smelting
Last Answer : (B) Roasting
Description : Pick up the correct statement from the following: (A) Roasting is not necessary if iron ore is an oxide (B) Impurities float on the molten iron as slag (C) The slag contains lime about 45% (D) All the above
Description : If the iron ore contains clay as an impurity, the flux added during calcination, is (A) Clay (B) Lime stone (C) Argillaceous iron ore (D) All the above
Last Answer : Answer: Option B
Description : Drossing is a __________ operation. (A) Smelting (B) Dressing (C) Roasting (D) Dressing
Last Answer : (C) Roasting
Description : Which of the following is an ore dressing operation? (A) Classification (B) Smelting (C) Roasting (D) None of these
Last Answer : Option A
Description : Heating of a ore below its melting point in the absence of air is known as – (1) Refining (2) Calcination (3) Roasting (4) Smelting
Last Answer : (2) Calcination Explanation: Calcination involves simple decomposition of ore on heating below its melting point usually in absence of air to produce new compounds having higher percentage of ... as removing the moisture, organic matter and volatile impurities. Calcination makes the ore porous.
Description : Heating of a ore below its melting point in the absence of air is known as (1) Refining (2) Calcination (3) Roasting (4) Smelting
Last Answer : Calcination
Description : Washing of coal is done to reduce the (A) Inherent impurities (B) Adhering impurities (C) Mineral matter (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Difference between Calcination and Roasting.
Last Answer : Calcination Roasting 1)Process of heating the ore strongly in absence of air below its M.P 1)Process of heating the ore strongly in presence of air below its M.P. 2)This ... the doors are kept opened. 6. Decomposition reaction takes place 6.Oxidation reaction takes place
Description : In extraction of metal how many of the following ores calcination process is involved . (i) Dolomite (ii) Malachite (iii) Calcite (iv) Copper pyrities
Last Answer : In extraction of metal how many of the following ores calcination process is involved . (i) Dolomite ... Siderite (viii) Iron pyrite (ix) Ar gentite
Description : To which of the following ores , calcination process is not applicable
Last Answer : To which of the following ores , calcination process is not applicable A. Zns B. `Al_(2)O_(3)2H_(2)O` C. `CuCO_(3).Cu(OH)_(2)` D. `CaCO_(3)`
Description : Hydraulic lime is obtained by (A) Burning of lime stone (B) Burning of kankar (C) Adding water to quick lime (D) Calcination of pure clay
Description : Which of the following faction is of no significance for roasting sulphide ores to the oxide and not subjecting the sulphide ores in carbon reduction
Last Answer : Which of the following faction is of no significance for roasting sulphide ores to the oxide and ... are thermodynamically more stable than `CS_(2)`
Description : Reverberatory furnace is used for (A) Roasting/reduction of ores (B) Annealing steel coil (C) Heating air (D) Steel melting
Last Answer : (A) Roasting/reduction of ores
Description : Unreacted core model' represents the reaction involving (A) Combustion of coal particles (B) Roasting of sulphide ores (C) Manufacture of carbon disulphide from elements (D) None of these
Last Answer : (B) Roasting of sulphide ores
Description : Concentration of sulphide ores is done usually by (A) Roasting (B) Smelting (C) Froth floatation (D) Electromagnetic separation
Last Answer : (C) Froth floatation
Description : Roasting of metallurgical ores is done mainly to (A) Dehydrate it (B) Sinter the ore (C) Remove CO2 & H2O (D) Remove arsenic & sulphur
Last Answer : (D) Remove arsenic & sulphur
Description : Assertion: `Ag` and `Au` are extracted by leaching the ores with a dilute solution of `NaCN`. Reason: Impurities associated with these ores dissolve i
Last Answer : Assertion: `Ag` and `Au` are extracted by leaching the ores with a dilute solution of `NaCN`. ... . Statement-1 is false but Statement -2 is true
Description : Impurities in metal ores are called: w) flux x) gangue (pron: gang) y) slag z) sediments
Last Answer : ANSWER: X -- GANGUE
Description : Pick up the correct statement from the following: (A) Quick lime is obtained by burning pure lime stone (B) Hydraulic lime is obtained by burning lime stone containing clay 5% to 30% (C) Poor lime is obtained by burning lime stone containing impurities more than 5% (D) All the above
Description : Pig iron made from haematite ores free from sulphur, phosphorus and copper, is known as (A) Bessemer pig (B) Grey or foundry pig (C) White or forge pig (D) Mottled pig
Last Answer : Answer: Option A
Description : Pick up the correct statement from the following: (A) The heating of a material to redness in contact with air, is known as calcination (B) The property of lime by which it sets or hardens in ... (C) The product that remains after calcination of limestone, is called lime (D) All the above
Description : Sweetening of petroleum product means the removal of (A) Sulphur & its compounds (B) Water (C) Organic impurities (D) Wax
Last Answer : (A) Sulphur & its compounds
Description : Which of the following processes is not an example of adsorption applied to gaseous separations? (A) Recovery of valuable solvent vapors from dilute mixture with air and ... Removal of objectionable odour and impurities from industrial gases (D) Decolouration of yellow glycerine
Last Answer : (D) Decolouration of yellow glycerine
Description : Most widely and commonly used coagulant for the removal of suspended impurities in water is (A) Bleaching powder (B) Slaked lime (C) Alum (D) Copper sulphate
Last Answer : (C) Alum
Description : Hydrazine is used in water treatment for the removal of (A) Colloidal impurities (B) Dissolved oxygen (C) Turbidity (D) Chlorinous taste
Last Answer : (B) Dissolved oxygen
Description : The correct sequence of steps involved in extraction of metal from its ore is a) removal of impurities, purify metal, reduction of ore b) purify metal, removal of impurities, reduction of metal ore . c ... of metal , reduction d) removal of impurities from ore , reduction of ore , refining of metal
Last Answer : d) removal of impurities from ore , reduction of ore , refining of metal
Description : Pick up the correct statement from the following: (A) In basic Bessemer process, the steel heats the converter (B) In open-hearth process, the furnace heats the steel (C) In Siemens process, the impurities of pig iron are oxidised by the oxygen of the ore (D) All the above
Description : Cast iron (A) Is obtained by purifying pig iron (B) Is manufactured in required shapes (C) May contain 2 to 5 per cent of carbon with other impurities (D) All the above
Description : Carl Heinrich Theodor ____ married well, and was thus able to go into business in 1838. He set up a coffee and chicory roasting operation. His sons hit upon ways of selling bean, pea, ... , and that eventually led them to the distinctive product now associated with their surnames. What surname?
Last Answer : Knorr.
Description : Portland cement manufactured from pure white chalk and clay but free from iron-oxide, is known as (A) Quick setting cement (B) Rapid hardening cement (C) White cement (D) Low heat Portland cement
Last Answer : Answer: Option C
Description : The process of manufacturing steel by heating short lengths of wrought iron bars mixed with charcoal in fire clay crucibles and collecting the molten iron into moulds, is known as (A) Cementation process (B) Crucible process (C) Bessemer process (D) Open hearth process
Description : Pick out the wrong statement: (A) Magnetic separation method can be employed to treat both dry & wet ores (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed ... ) Gyratory crusher is used for coarse crushing (D) Screens are of stationary, moving and vibratory types
Last Answer : (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed size to the maximum product size
Description : Quick lime (or caustic lime) (A) Is obtained by the calcination of pure lime stone (B) Has great affinity to moisture (C) Is amorphous (D) All the above
Description : Which is not a possible cause of optical fiber loss? ∙ a. Impurities ∙ b. Glass attenuation ∙ c. Stepped index operation ∙ d. Microbending
Last Answer : ∙ c. Stepped index operation
Description : Iron ore hematite is concentrated using (A) Electromagnetic separation mainly (B) Gravity separation (C) Froth floatation (D) Roasting
Last Answer : (B) Gravity separation
Description : Coal washing waste water containing about 3% suspended solids (comprising of clay, slate, stone etc.) is treated for solid particles removal (A) By chemical coagulation (B) In sedimentation tanks equipped with mechanical scrapper (C) In vacuum filter (D) In clarifiers
Last Answer : (B) In sedimentation tanks equipped with mechanical scrapper
Description : The preparation of surface of stone to obtain plain edges or to obtain stones of required size and shape is known as (A) Quarrying of stones (B) Blasting of stones (C) Seasoning of stones (D) Dressing of stones
Description : The commodity which accounts for the maximum volume of goods transported by the railways in India is (a) iron and steel (b) coal (c) mineral oil (d) metallic ores (other than iron ore)
Last Answer : Ans: (b)
Description : Which of the following ores does not contain iron? (1) Haematite (2) Magnetite (3) Limonite (4) Cassiterite
Last Answer : (4) Cassiterite
Description : Froth floatation is the most suitable for treating (A) Iron ores (B) Sulphide ores (C) Quartzite (D) None of these
Last Answer : (B) Sulphide ores
Description : Stamp mills are generally used for crushing (A) Iron ores (B) Gold ores (C) Talc (D) Diamond
Last Answer : (B) Gold ores
Description : At a site, low grade copper ores are available and zinc and iron seraps are also available. Which of the two seraps will be more suitable for reducing the leached copper ore and why ?
Last Answer : Ans. : The E0 value for the redox couple Zn2+/ Zn(-0.76V) is more negative than that of Fe2+/ Fe(- 0.44) redox couple. Therefore, Zinc is more reactive than iron and hence reduction will ... Zinc seraps are used, But Zinc is a costier metal than iron so using iron scraps would be more economical.
Description : Which of the following is the primary reason for adding calcium carbonate to the reduction process of iron oxide ores ? The calcium carbonate: w) acts as an oxidizing agent x) removes silicate waste products y) acts as a reducing agent z) removes sulfur waste products
Last Answer : ANSWER: X -- REMOVES SILICATE WASTE PRODUCTS
Description : Write two ores of iron with chemical formula.
Last Answer : 1) Magnetite - Fe₃O₄ 2) Haematite - Fe₂O₃ 3) Limonite - 2 Fe₂O₃.3H₂O 4) Iron Pyrites - FeS₂ 5) Siderite - FeCO₃
Description : Among the following iron ores, the highest percentage of iron content is found in— (1) Haemetite (2) Magnetite (3) Limnonite (4) None of these
Last Answer : Haemetite
Description : Name two important ores of iron? Mention its formula.
Last Answer : Name two important ores of iron? Mention its formula.