Description : Theoretical volume of oxygen required for complete combustion of 1Nm3 of acetylene, in oxy-acetylene welding is __________ Nm3. (A) 0.5 (B) 1 (C) 1/3 (D) 2.5
Last Answer : Option D
Description : Oxygen required for theoretically complete combustion of 1 Nm3 methane is __________ Nm3 . (A) 2 (B) 4 (C) 6 (D) 1
Last Answer : (A) 2
Description : Which of the following will generate maximum volume of product of complete combustion (Nm3 /Nm3 of fuel)? (A) Carburetted water gas (B) Blast furnace gas (C) Natural gas (D) Producers' gas
Last Answer : (C) Natural gas
Description : Stoichiometric combustion of 12 kg of carbon requires __________ of oxygen. (A) 1kg mole (B) 22.4 Nm3 (C) 32 kg (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Dry air requirement for burning 1 Nm3 of CO to CO2 may be around __________ Nm3 . (A) 2.4 (B) 1.75 (C) 0.87 (D) 11.4
Last Answer : (A) 2.4
Description : Which of the following fuel gases will require maximum amount of air for combustion of 1 Nm3 gas? (A) Blast furnace gas (B) Natural gas (C) Producer gas (D) Water gas
Last Answer : (B) Natural gas
Description : The main function of primary air in pulverised coal fired burner is to (A) Burn CO to CO2 (B) Dry and transport the coal (C) Have proper combustion by supplying it around the burner (D) Preheat the tertiary air used for complete combustion of CO to CO2
Last Answer : (B) Dry and transport the coal
Description : One kg of carbon for theoretically complete combustion requires __________ kg of air. (A) 11.5 (B) 0.5 (C) 23 (D) 12
Last Answer : (A) 11.5
Description : Flue gas obtained on complete combustion of pure acetylene (a hydrocarbon fuel) will contain (A) CO (B) CO2 (C) H2O (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
Description : The air requirement of a petrol engine during starting compared to theoretical air required for complete combustion is a. more b. less c. same d. may be more or less depending on engine capacity
Last Answer : ANSWER b. less
Description : The excess air required for the combustion of pulverised coal is of the order of about __________ percent. (A) 5 (B) 15 (C) 30 (D) 45
Last Answer : (B) 15
Description : Ammonia content in raw coke oven gas is about __________ gm/Nm3 . (A) 1 (B) 5 (C) 50 (D) 100
Last Answer : (B) 5
Description : Calorific value of gobar gas (containing CH4 = 60% , H2 = 10% ; CO2 = 30%) may be about __________ Kcal/Nm3 . (A) 1,800 (B) 3,200 (C) 5,400 (D) 10,200
Last Answer : (C) 5,400
Description : Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm3 /ton of dry coal. (A) 60 (B) 160 (C) 500 (D) 750
Last Answer : (B) 160
Description : C.V. (kcal/Nm3 ) of gaseous fuels __________ with increase in molecular weight. (A) Decreases (B) Increases (C) Remain constant (D) May increase or decrease, depends on combustibles
Last Answer : (D) May increase or decrease, depends on combustibles
Description : Calorific value of wood gas is about __________ kcal/Nm3 . (A) 1500 (B) 3300 (C) 5400 (D) 8500
Last Answer : (B) 3300
Description : Dust content in raw blast furnace gas is about __________ gm/Nm3 ; hence it is cleaned to the dust level of about < 10 mg /Nm3 before use. (A) 15-30 (B) 1-2 (C) 70-100 (D) 150-200
Last Answer : (A) 15-30
Description : The calorific value of natural gas is about __________ kcal/Nm3 . (A) 10,000 (B) 2,500 (C) 25,000 (D) 35,000
Last Answer : (A) 10,000
Description : Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around __________ Nm3 . (A) 30 (B) 300 (C) 3,000 (D) 30,000
Last Answer : (B) 300
Description : Yield of blast furnace gas is about __________ Nm3 /ton of pig iron. (A) 300 (B) 2000 (C) 5000 (D) 10000
Last Answer : (B) 2000
Description : The calorific value of L.D. converter gas is about __________ Kcal/Nm3 . (A) 1800 (B) 800 (C) 4500 (D) 10000
Last Answer : (A) 1800
Description : The calorific value of producer gas is around __________ kcal/Nm3 . (A) 1300 (B) 500 (C) 4500 (D) 9000
Last Answer : (A) 1300
Description : Calorific value of coke even gas produced by low temperature carbonisation of coal is about __________ Kcal/Nm3 . (A) 4000 (B) 2500 (C) 6500 (D) 10000
Last Answer : (C) 6500
Description : Gas yield in the Kopper-Totzek coal gasifier is about __________ Nm3 /ton coal (ash = 35%). (A) 150 (B) 1500 (C) 3500 (D) 5000
Last Answer : (C) 3500
Description : The calorific value of 'LPG' (50% propane + 50% butane) is about __________ kcal/Nm3 . (A) 5000 (B) 25,000 (C) 10,000 (D) 15,000
Last Answer : (B) 25,000
Description : Calorific value of coke oven gas is around __________ Kcal/Nm3 . (A) 900 (B) 4200 (C) 7500 (D) 2000
Last Answer : (B) 4200
Description : Calorific value of blast furnace gas is around __________ KCal/Nm3 . (A) 850 (B) 1800 (C) 4200 (D) 6500
Last Answer : (A) 850
Description : Pick out the wrong statement. (A) The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are the same for NSc = NPr= 1 (B) 1 Nm3 of dry air is lighter ... ) The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity
Last Answer : (B) 1 Nm3 of dry air is lighter than 1Nm3 of humid air
Description : Pick out the wrong statement. (A) Main constituents of LPG are propane and butane (B) C.V. of natural gas is about 10000 KCal/Nm3 (C) C.V. of LPG is about 26000 kcal/Nm3 (11500 kcal/kg) (D) L.P.G. is lighter than air
Last Answer : (D) L.P.G. is lighter than air
Description : At `25^(@)` C for complete combustion of 5 mol propane `(C_(3)H_(8))` . The required volume of `O_(2)` at STP will be .
Last Answer : At `25^(@)` C for complete combustion of 5 mol propane `(C_(3)H_(8))` . The required volume of `O_(2)` at ... . A. 560 L B. 560 mL C. 360 L D. 360 mL
Description : Air/gas ratio for complete combustion will be the highest for (A) LPG (B) Gobar gas (C) Coke oven gas
Last Answer : (A) LPG
Description : Preheating of combustion air is done to (A) Increase the adiabatic flame temperature (B) Increase the calorific value of the fuel (C) Complete the combustion of fuel (D) Reduce its requirement for effecting the complete combustion
Last Answer : (A) Increase the adiabatic flame temperature
Description : Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to ... coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG
Last Answer : (D) Calorific value of natural gas is more than that of LPG
Description : Which of the following would require maximum amount of % excess air for complete combustion? (A) Coke oven gas (B) Furnace oil (C) Pulverised coal (D) Lump coal (fixed on chain grate)
Last Answer : (D) Lump coal (fixed on chain grate)
Description : A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has ... (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion
Last Answer : (C) Complete combustion of fuel has taken place
Description : Supply of excess air for complete combustion of fuel is necessitated to facilitate (A) Its thorough mixing with air (B) Attainment of chemical equilibrium (C) Attainment of high temperature (D) None of these
Last Answer : (A) Its thorough mixing with air
Description : Incomplete combustion of fuel in the furnace is judged by high __________ of the flue gases. (A) CO content (B) Dew point (C) CO2 content (D) O2 content
Last Answer : (A) CO content
Description : __________ the exhaust gas is an indication of the incomplete combustion of fuel. (A) Low temperature of (B) High temperature of (C) High % of CO in (D) High % of CO2in
Last Answer : (C) High % of CO in
Description : At STP , for complete combustion of 3 g `C_(2)H_(6)` the required volume of `O_(2)` will be -
Last Answer : At STP , for complete combustion of 3 g `C_(2)H_(6)` the required volume of `O_(2)` will be - A. 78. 4 L B. 7. 84 L C. 2. 78 L D. 6. 23 L
Description : Volumetric composition of flue gas analysed with the Orsat apparatus is : CO2 = 12%, O2 = 8%, CO = nil, N2 = 80%. This flue gas composition indicates that (A) Pure oxygen has been used for combustion ... very high (C) Excess air has been used for combustion (D) Hydrogen is not present in the fuel
Last Answer : (C) Excess air has been used for combustion
Description : The air requirement of a petrol engine during starting compared to the theoretical air requirement for complete combustion is A. more B.unpredictable C. same D. less
Last Answer : ANSWER : D
Description : Combustion of furnace oil in a furnace (soaking pit) with preheated combustion air at 400°C results in saving of about __________ percentfurnace oil as compared to its combustion with atmospheric air, if the flue gas outlet temperature from the soaking pit is 1200°C. (A) 5 (B) 60 (C) 20 (D) 40
Last Answer : (C) 20
Description : Furnace oil consumption in a furnace for a given duty employing preheated combination air (at 300°) may be reduced by about __________ percent as compared to the use of atmospheric combustion air. (A) 5 (B) 10 (C) 20 (D) 35
Description : Which of the following has the least calorific value (kcal/Nm3 )? (A) Blast furnace gas (B) Coke oven gas (C) Sewage gas (D) Natural gas
Last Answer : (A) Blast furnace gas
Description : Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches ... about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil
Last Answer : (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point
Description : For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3 ), while the C.V. is same on weight basis (i.e., kcal/kg)? (A) Propane and acetylene (B) Propane and LPG (C) Sewage gas and gobar gas (D) B.F. gas and coke oven gas
Last Answer : (A) Propane and acetylene
Description : Pick out the wrong statement. (A) Percentage of ash in coke produced from medium coking coal is more than that in coal (B) The calorific value (kcal/Nm3 ) of coke oven gas reduces on ... plants in India at Talcher (Orissa) and Ramagundam (A.P) employ Kopper-Totzek process of coal gasification
Last Answer : (C) Ash is normally removed as 'fly-ash' in Kopper-Totzek process of coal gasification
Description : Which of the following has the highest calorific value (kcal/Nm3 )? (A) Carburetted water gas (B) Gobar gas (C) Natural gas (D) LPG
Last Answer : (D) LPG
Description : In low temperature carbonisation of coal, the (A) Yield of coke oven gas is 290 Nm3 /ton dry coal (B) Volatile matter in coke is zero (C) Temperature maintained is 700°C (D) Yield of tar is about 3% of dry coal
Last Answer : (C) Temperature maintained is 700°C
Description : Which of the following gaseous fuels has the highest net calorific value (kcal/Nm3 )? (A) Producer gas (B) Carburetted water gas (C) Natural gas (D) Liquefied petroleum gas
Last Answer : (D) Liquefied petroleum gas