Description : Gray King Assay and Swelling Index of a coal is a measure of its (A) Swelling characteristics (B) Abradability (C) Agglutinating properties (D) Resistance to impact breakage
Last Answer : (A) Swelling characteristics
Description : Which of the following is a measure of the agglutinating (i.e., binding) property of coal? (A) Thickness of plastic layer (B) Caking index (C) Swelling index (D) Gray-king index
Last Answer : (B) Caking index
Description : "Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength
Last Answer : (D) Hardness & strength
Description : Pick out the wrong statement. (A) Indian coals on an average contain 25-30% ash as against 10-12% ash in imported coking coal (B) Ammonia is recovered in the form of ammonium sulphate in direct ... indicates poor caking properties of coal (D) Wash oil is used for scrubbing Benzol from coke oven gas
Last Answer : (C) A high swelling index number of coking coal indicates poor caking properties of coal
Description : The weathering index of a coal (A) Gives an idea of the fusion temperature of ash (B) Is related to its calorific value (C) Is a measure of its size stability, when stored & exposed to weather (D) Is a measure of its caking tendency
Last Answer : (C) Is a measure of its size stability, when stored & exposed to weather
Description : Mott and Wheeler test is conducted on coke to find its (A) Reactivity with O2 (B) Abradability (C) Phosphorus content (D) Volatile matter content
Last Answer : (A) Reactivity with O2
Description : Highly reactive coke have lower (A) Porosity (B) Coke reactivity index (CRI) (C) Critical air blast (CAB) value (D) Both (B) and (C)
Last Answer : (C) Critical air blast (CAB) value
Description : Improper storage condition results in the weathering of coal and spontaneous combustion, which increases its (A) Caking index (B) Yield of carbonised products (C) Friability & oxygen content (D) Calorific value
Last Answer : (C) Friability & oxygen content
Description : Washing of coal decreases its (A) Caking index (B) Mineral matter content (C) Ash content (D) Both (B) and (C)
Last Answer : (B) Mineral matter content
Description : A coal having higher volatile matter content will necessarily have lower (A) Ash fusion temperature (B) Calorific value (C) Ignition temperature (D) Caking index
Last Answer : (C) Ignition temperature
Description : Caking index of the coal blend used for the manufacture of metallurgical coke should be around (A) 5 (B) 21 (C) 40 (D) 48
Last Answer : (B) 21
Description : Caking index of coal blend used for blast furnace coke making is about (A) 8 (B) 12 (C) 22 (D) 36
Last Answer : (C) 22
Description : __________ of the coal is the basis for Seylor's coal classification. (A) Proximate analysis (B) Ultimate analysis (C) Caking index (D) Calorific value
Last Answer : (B) Ultimate analysis
Description : With increase in moisture content of coal, its (A) Calorific value increases (B) Caking properties diminish (C) Swelling during carbonisation becomes excessive (D) None of these
Last Answer : (B) Caking properties diminish
Description : Softening temperature of coal ash is a measure of the __________ of coal. (A) Caking tendency (B) Coking tendency (C) Clinkering tendency (D) Size stability
Last Answer : (C) Clinkering tendency
Description : Shatter index of the coke is a measure of its (A) Strength (B) Bulk density (C) Reactivity (D) None of these
Last Answer : (A) Strength
Description : Pick out the wrong statement. (A) Cokes of high reactivity are obtained from weakly coking coals (B) Cokes of high reactivity are obtained from strongly coking coals (C) Reactivity of coke is inversely proportional to its absolute density (D) Abrasion index of the coke is a measure of its hardness
Last Answer : (B) Cokes of high reactivity are obtained from strongly coking coals
Description : Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Low temperature oxidation of coal during storage does not decrease its (A) Oxygen content (B) Caking power (C) Calorific value (D) None of these
Last Answer : (D) None of these
Description : Low temperature oxidation of coal resulting from bad storage conditions does not decrease its (A) Caking power (B) Calorific value (C) Hydrogen content (D) Oxygen content
Last Answer : (D) Oxygen content
Description : Weathering of coal during storage causes (A) Reduction in coal size (B) Increase in its friability (C) Decrease in its caking capacity (D) All (A), (B) and (C)
Description : Low temperature oxidation of stored coal results in the (A) Decrease in its caking power & calorific value (B) Decrease in its carbon & hydrogen content (C) Increase in its oxygen content (D) All (A), (B) and (A)
Last Answer : (D) All (A), (B) and (A)
Description : With increase in the oxygen content of the coal, its __________ decreases. (A) Calorific value (B) Caking power (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : Coals used for the generation of producer gas should have (A) High caking index (B) Low fusion point of ash (C) High volatile matter content (D) Very low ash content (8-10%)
Last Answer : (C) High volatile matter content
Description : Caking coal is desirable for (A) Burning on travelling grate (B) Coke making (C) Burning on firebars (D) All (A), (B) and (C)
Last Answer : (B) Coke making
Description : A coal that softens and fuses on heating is (A) Classified (B) Carbonised (C) Caking (D) Non-caking
Last Answer : (C) Caking
Description : A travelling grate stoker is meant for the efficient burning of __________ coal. (A) Caking (B) Pulverised (C) Non-caking (D) High ash
Last Answer : (C) Non-caking
Description : Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C ... capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)
Description : Which of the following fuels is the best for burning on chain grate stoker? (A) Non-caking coal (B) Caking coal (C) Coking coal (D) Pulverised coal
Last Answer : (A) Non-caking coal
Description : Pick out the wrong statement. (A) Strongly caking coal should not be used in the Lurgi gasifier (B) Acetylene gas cannot be used for illumination purpose (C) Water gas is called blue gas ... is burnt (D) Gaseous fuels require less percentage of excess air for combustion as compared to liquid fuels
Last Answer : (B) Acetylene gas cannot be used for illumination purpose
Description : Which of the following accentuates clinkering troubles on furnace grate burning coal? (A) Low reactivity of carbonised residue containing high proportion of iron & sulphur (B) Low forced draft & fuel bed temperature (C) Thick firebed and preheated primary air (D) All (A), (B) and (C)
Description : Which of the following accentuates clinkering trouble on furnace grate burning coal? (A) Low reactivity of carbonised residue containing high proportions of iron & sulphur (B) Low forced draught and fuel bed temperature (C) Thick fire bed and preheated primary air (D) All (A), (B) and (C)
Description : Critical Air Blast (CAB) value of coke is a direct measure of its (A) Reactivity (B) Hardness (C) Strength (D) None of these
Last Answer : (A) Reactivity
Description : During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the __________ of the mass. (A) Density (B) Porosity (C) Electrical resistivity (D) None of these
Last Answer : (A) Density
Description : Helium (He), neon (Ne) and argon (Ar) are all colorless, odorless gases with low chemical reactivity. Based on the periodic table, which other element would also have those same properties?
Last Answer : Helium
Description : Refractory metals are known for which of the following properties: w) lack of chemical reactivity x) low density y) high melting point z) high thermal conductivity
Last Answer : ANSWER: Y -- HIGH MELTING POINT
Description : Coal tar is used as a (A) Binding material for coal briquettes (B) Fuel in rotary kiln (C) Binder in making carbon electrodes (D) All (A), (B) and (C)
Description : Fat coals' are those coals which have very high (A) Caking capacity (B) Volatile matter content (C) Fusion point of its ash (D) Inherent moisture conten
Last Answer : (A) Caking capacity
Description : Conditioners like finely divided peat are added to the fertiliser to (A) Counteract burning (B) Avoid caking & hardening (C) Produce bulk (D) Increase its solubility
Last Answer : (B) Avoid caking & hardening
Description : The caking of crystals can be prevented by (A) Maintaining high critical humidity (B) Maintaining low critical humidity (C) Coating the product with inert material (D) Both (A) and (C)
Last Answer : (D) Both (A) and (C)
Description : Powdery materials can be guarded against caking tendency on storage by (A) Providing irregular grain size (B) Providing minimum percentage of voids (C) Having maximum possible points of contact (D) None of these
Description : . Highly caking coals (A) Produce weak coke (B) Produce strong coke (C) May damage the coke oven walls during carbonisation (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Carbonisation of coal consists of A. drying and crushing the coal to a fine powder B. moulding the finely ground coal under pressure with or without a binding material C. heating the wood with a limited supply of air to temperature not less than 280°C D. none of the above
Last Answer : Answer: D
Description : A competitive inhibitor of an enzyme has which of the following properties? (A) It is frequently a feedback inhibitor (B) It becomes covalently attached to an enzyme (C) It decreases the Vmax (D) It interferes with substrate binding to the enzyme
Last Answer : Answer : D
Description : Pick out the wrong statement. (A) Angle of repose of coal increases with its increasing size (B) Specific gravity of coal increases with its increasing maturity (C) Refractive index and reflectance of ... of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal
Last Answer : (D) Specific heat of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal
Description : Grindability index of a coal is 100. It implies that the (A) Coal can be pulverised with great difficulty (B) Coal can't be pulverised (C) Coal can be easily pulverised (D) Power consumption in grinding the coal will be very high
Last Answer : (C) Coal can be easily pulverised
Description : Hardgrove Grindability index of four coal samples are given below. Which of them is the easiest to grind? (A) 50 (B) 70 (C) 85 (D) 100
Last Answer : (D) 100
Description : Washing of coal (A) Reduces its sulphur and ash content (B) Controls its ash fusibility and increases its calorific value (C) Improves its coking properties (D) All (A), (B) and (C)
Description : Washing of coal (A) Reduces its ash & sulphur content (B) Improves its coking properties (C) Increase the fusion point of its ash by removing chlorine compounds (D) All (A), (B) and (C)
Description : The intensive properties are (A) Molar volume, density, viscosity and boiling point (B) Refractive index and surface tension (C) Both (A) and (B) (D) None of these
Last Answer : (C) Both (A) and (B)