Description : Calcination reaction of limestone (CaCO3 → CaO + CO2 ) goes to completion in the rotary kiln, because (A) CaO is not dissociated (B) CO2 escapes continuously (C) Of high calcination temperature (D) CaO is more stable than CaCO3
Last Answer : (B) CO2 escapes continuously
Description : How much temperature is maintained during quicklime manufacture in the calcination zone of the vertical shaft kiln? (A) 500°C (B) 750°C (C) 1000°C (D) 1500°C
Last Answer : (C) 1000°C
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 : How many of the following statement is /are ture for calcination of metal ore ?
Last Answer : How many of the following statement is /are ture for calcination of metal ore ? A. (i) It makes ... of crystlliation D. Impurities of S,As and Sb are
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 : The ultrapure metal is obtained by - (1) Calcination (2) Sublimation (3) zone refining (4) None of these
Last Answer : (3) zone refining Explanation: The principal stages in the production of ultrapure metals are the preparation of pure chemical compounds, the reduction of the compounds to the elementary state and further purification.
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 : What do you mean by calcination?
Last Answer : Heating in the absence of ai
Last Answer : Coating iron with Zinc
Description : Calcination of limestone to produce lime is done in a __________ kiln. (A) Tunnel (B) Rotary (C) Vertical shaft (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent. (A) 20 (B) 40 (C) 65 (D) 80
Last Answer : (B) 40
Description : Rotary kilns are used in the (A) Calcination of limestone & dolomite (B) Cement manufacture (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Reducing atmosphere is maintained in a (A) Calcination kiln (B) Blast furnace (C) Soaking pit (D) L.D. converter
Last Answer : (B) Blast furnace
Description : Which of the following is not a directly fired furnace? (A) By-product coke oven (B) Calcination kiln (C) Sintering furnace (D) Open hearth furnace
Last Answer : (A) By-product coke oven
Description : Which of the following is used for calcination of limestone and dolomite in industrial practice? (A) Fluidised bed reactor (B) Moving bed reactor (C) Fixed bed reactor (D) None of these
Last Answer : (B) Moving bed reactor
Description : In case of calcination of limestone, CaCO3 CaO + CO2 , the addition of more of CaO will result in __________ in the concentration of CO2 . (A) No change (B) Increase (C) Decrease (D) Unpredictable from the data
Last Answer : (A) No change
Description : Calcination of gypsum produces (A) Plaster of Paris (B) Salt cake (C) Nitre cake (D) Lime
Last Answer : (A) Plaster of Paris
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 : Calcination of limestone is not done in a __________ kiln for producing lime. (A) Vertical shaft (B) Rotary (C) Fluidised bed (D) Fixed bed
Last Answer : (D) Fixed bed
Description : The operation of removal of impurities or clay adhering to iron ores, is known as (A) Dressing (B) Calcination (C) Roasting (D) Smelti
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
Last Answer : Answer: Option D
Description : Pig iron is manufactured from the ores by (A) Dressing (B) Calcination and roasting (C) Smelting (D) All the above
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 : 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 : 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 : Explain following unit process with example. (i) Reduction (ii) Calcination (iii) Nitration
Last Answer : Reduction: Reduction is defined as the addition of hydrogen, removal of oxygen, addition of metallic element or addition of electrons. Eg. Reduction of ethyl bromide Nitrobenzene can be reduced ... Sulfuric acid and con. Nitric acid. Nitrating mixture is used in nitration reaction.
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 : 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 : During photorespiration, the oxygen consuming reaction (s) occur in
Last Answer : During photorespiration, the oxygen consuming reaction (s) occur in A. Grana of ... mitochondria D. Stroma of chloroplasts and peroxisomes
Description : During photorespiration, the oxygen consuming reaction(s) occur in (a) stroma of chloroplasts (b) stroma of chloroplasts and mitochondria (c) stroma of chloroplasts and peroxisomes (d) grana of chloroplasts and peroxisomes.
Last Answer : (c) stroma of chloroplasts and peroxisomes
Description : During metamorphonism, changes in the bulk composition of a rock occur primarily as a result of _____? a) Increase in pressure b) Increases in temperature c) Reaction with hydrothermal fluids d) All of these
Last Answer : Increase in pressure