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 : A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large ... fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air
Last Answer : (D) Lack of thorough mixing of fuel with air
Description : Oxygen content in a flue gas was found to be 4%. It implies that excess air used for combustion was around __________ percent. (A) 4 (B) 96 (C) 20 (D) 40
Last Answer : (C) 20
Description : A sample of natural gas containing 80% methane (CH4 ) and rest nitrogen (N2 ) is burnt with 20% excess air. With 80% of the combustibles producing CO2 and the remainder going to CO, the Orsat analysis in volume percent is (A) CO2 : 6 ... 96, N2 :72.06 (D) CO2 : 7.60, CO : 1.90, O2 : 4.75, N2 : 85.74
Last Answer : (B) CO2 : 7.42, CO : 1.86, O2 : 4.64, N2 :86.02
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 : 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 : Ostwald charts are meant for (A) Computing the excess/deficiency of combustion air (B) Calculation of flue gas temperature (C) Computation of flue gas analysis (D) None of these
Last Answer : (A) Computing the excess/deficiency of combustion air
Description : A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted
Last Answer : (C) Same
Description : Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent. (A) < 2 (B) < 5 (C) < 8 (D) < 10
Last Answer : (A) < 2
Description : Pick out the wrong statement. (A) Pulverised fuel can be completely burnt with less percentage of excess air compared to lump coal (B) Low grade coal can be used, but generally high volatile ... and atmosphere (oxidising or reducing) is easily possible with pulverised fuel firing (D) None of these
Last Answer : (D) None of these
Description : Too much of excess air in combustion results in high (A) Fuel consumption for the same heat load (B) Stack gas temperature (C) Percentage of oxygen in flue gases (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : In flue gas analysis by Orsat's apparatus, oxygen is absorbed by (A) Potassium hydroxide (B) Cuprous chloride (C) Alkaline pyrogallol solution
Last Answer : (C) Alkaline pyrogallol solution
Description : In flue gas analysis by Orsat's apparatus, carbon dioxide is absorbed by (A) Potassium hydroxide (B) Dilute potassium carbonate (C) Cuprous chloride (D) Alkaline pyrogallol solution
Last Answer : (A) Potassium hydroxide
Description : In flue gas analysis by Orsat's apparatus, carbon monoxide is absorbed by (A) Cuprous chloride (B) Potassium hydroxide (C) Alkaline pyrogallol solution (D) None of these
Last Answer : (A) Cuprous chloride
Description : Theoretical flame temperature of a fuel is that temperature which is attained, when the fuel is completely burnt 'using theoretical amount of air in (A) Air (B) Oxygen (C) Either (A) or (B) (D) Either (A) or (B) without gain or loss of heat
Last Answer : (D) Either (A) or (B) without gain or loss of heat
Description : Incomplete combustion of a fuel is characterised by the high __________ in the flue gas. (A) Smoke (B) Temperature (C) Oxygen (D) Carbon monoxide
Last Answer : (D) Carbon monoxide
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 : Orsat apparatus (A) Gives flue gas analysis on dry basis (B) Determines N2 in flue gas indirectly (C) Can’t determine CO in flue gas, if it is < 0.2% (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : In order to maintain an oxidising atmosphere in a furnace, it should have (A) More of excess air (B) Less of excess air (C) More of CO in flue gas (D) More of CO2 in flue gas
Last Answer : (A) More of excess air
Description : In order to maintain a reducing atmosphere in a furnace, it should have (A) No O2 in flue gas (B) CO in flue gas (C) High excess air (D) None of these
Last Answer : (B) CO in flue gas
Description : The main drawback of supplying more excess air in the combustion of fuel is the (A) Excessive power requirement of air blower (B) Enhanced sensible heat loss in the flue gas (C) Intermittent and uncontrolled combustion of the fuel (D) High exit flue gas temperature from the furnace
Last Answer : (B) Enhanced sensible heat loss in the flue gas
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 : 6 gm of carbon is burnt with an amount of air containing 18 gm oxygen. The product contains 16.5 gms CO2 and 2.8 gms CO besides other constituents. What is the degree of conversion on the basis of disappearance of limiting reactant? (A) 100% (B) 95% (C) 75% (D) 20%
Last Answer : (B) 95%
Description : Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is __________ percent. (A) < 37% (B) > 71% (C) In between 37 & 71% (D) None of these
Last Answer : (C) In between 37 & 71%
Description : Orsat apparatus is meant for (A) Gravimetric analysis of flue gas (B) Finding out combustion efficiency (C) Direct determination of nitrogen in flue gas by absorbing it in ammoniacal cuprous chloride (D) None of these
Description : The sequence of absorption in flue gas analysis by Orsat's apparatus is respectively (A) CO2 , O2 , CO (B) CO, O2 , CO2 (C) CO2 , CO, O2
Last Answer : (A) CO2 , O2 , CO
Description : When incomplete combustion loss is high, the flue gas analysis shows large amount of (A) CO2 (B) CO (C) O2 (D) C
Last Answer : (B) CO
Description : Pick out the wrong statement. (A) Theoretical flame temperature is the temperature attained by the products of combustion, when the fuel is burned without loss or gain of heat (B) ... flame temperature (D) Adiabatic flame temperatures of actual combustions are always less than the maximum values
Last Answer : (C) Burning the fuel with excess pure oxygen results in maximum theoretical flame temperature
Description : Oxygen enrichment of combustion air does not result in increase of the (A) Flame temperature (B) Oxygen in the flue gas (C) Stack loss (D) Heat transfer rate in the furnace
Last Answer : (B) Oxygen in the flue gas
Description : Out of the following fuels used in a furnace exhausting flue gas at a temperature of 600°C, the percentage stack loss will be maximum in case ofcomplete combustion of (A) Furnace oil with air (B) Furnace oil with oxygen (C) Blast furnace gas with air (D) Blast furnace gas with oxygen
Last Answer : (C) Blast furnace gas with air
Description : In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid ... of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace
Last Answer : (C) Imperfect mixing of fuel & air and infiltration of air
Description : Combustion of fuel in a furnace with oxygen enriched air results in higher (A) Flue gas volume (B) Flame temperature (C) Fuel consumption (D) Stack loss
Last Answer : (B) Flame temperature
Description : If oxygen content in the flue gas rises too high, fuel is being wasted by (A) Incomplete combustion (B) Dry gas/stack gas loss (C) Moisture loss (D) None of these
Last Answer : (B) Dry gas/stack gas loss
Description : During combustion of a gaseous fuel, the presence of a non-luminous flame is an indication of the (A) Incomplete combustion (B) Complete combustion (C) High oxygen in flue gas (D) None of these
Last Answer : (B) Complete combustion
Description : Can anyone help me with this? Chlorine and carbon monoxide gases are mixed in a 1.00L container and the following equilibrium is established: CO(g) + Cl2(g) COCl2(g).. Initially 1.5 mol of ... monoxide. At equilibrium, 0.8 mol of COCl2(g) was found. How do you calculate the percent reaction?
Last Answer : For a start, your equation isn't balanced; it should be Cl2 (Cl2, not 2Cl, because of HONClBrIF). Given this, if we assume the reaction goes to completion, 1.5 mol Cl2 will produce 1.5 mol ... .3% Incidentally, is that supposed to be CO or Co? It has no effect on the calculation, just curious.
Description : Green coal, in order to be burnt, must be (A) Heated sufficiently (B) Burnt in excess air (C) Heated to its ignition point (D) Burnt as powder
Last Answer : (C) Heated to its ignition point
Description : Flue gas discharge velocity through chimney of a big thermal power plant may be around __________ m/sec. (A) 0.5 (B) 10 (C) 50 (D) 500
Last Answer : (B) 10
Description : Calculate the recoverable waste heat (Q, in kCal/hour) from flue gases using the followingparameters: V (flow rate of the substance) 2000 m3/hr r (density of the flue gas): 0.9 kg/m3 Cp (specific heat ... (temperature difference): 120 oC h (recovery factor): 50% a. 21600 b. 43200 c. 25600 d. 34000
Last Answer : 21600
Description : measures oxygen and temperature of the flue gas. a) Fuel efficiency monitor. b) Combustion analyzer. c) Contact thermometer. d) Infrared thermometer.
Last Answer : Combustion analyzer
Description : Oxygen trim control strategy __ a. continuously measures the oxygen content in the flue gas b. adjusts the combustion air flow c. Continually tuning the air-fuel mixture. d. All of above
Last Answer : d. All of above
Description : The gas that causes suffocation and death when coal or coke is burnt in a closed room is - (1) Methane (2) Ethane (3) Carbon monoxide (4) Carbon dioxide
Last Answer : (3) Carbon monoxide Explanation: Exhaust fumes of motor cars, gases produced, from coal fire in a closed room and coal gas, all contain carbon monoxide, which is the cause of their ... is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.
Description : The gas that causes suffocation and death when coal or coke is burnt in a closed room is (1) Methane (2) Ethane (3) Carbon monoxide (4) Carbon di–oxide
Last Answer : Carbon monoxide
Description : The maximum adiabatic flame temperature is attained, when the fuel is burnt with (A) Theoretically required amount of air (B) More than theoretically required amount of air (C) Less than theoretically required amount of air (D) Theoretically required amount of oxygen
Last Answer : (D) Theoretically required amount of oxygen
Description : Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the (A) Calorific value (B) Heat of reaction (C) Heat of combustion (D) Heat of formation
Last Answer : (C) Heat of combustion
Description : 'Utilities' in a chemical process plant includes compressed air, steam, water, electrical power, oxygen, acetylene, fuel gases etc. Utility costs for ordinary chemical process plants ranges roughly from __________ percent of the total product ... 1 to 5 (B) 10 to 20 (C) 25 to 35 (D) 35 to 45
Last Answer : (B) 10 to 20
Description : The human brain uses----- percent of the total oxygen and blood in the body? A. 20 (Answer) B. 12 C. 35 D. 48
Last Answer : A. 20 (Answer)
Description : To convert volumetric analysis to gravimetric analysis, the relative volume of each constituent of the flue gases is (a) divided by its molecular weight (b) multiplied by its molecular weight (c) ... by its density (d) multiplied by its specific weight (e) divided by its specific weight.
Last Answer : Answer : b
Description : For every 10% increase in the excess air; the fuel consumption increases by __________ percent. (A) 0.1 (B) 0.2 (C) 0.5 (D) 1.0
Last Answer : (A) 0.1
Description : 0.6 g of carbon was burnt in the air to form `CO_(2)`. The number of molecules of `CO_(2)` introduced into the will be : `C+O_(2)toCO_(2)`
Last Answer : 0.6 g of carbon was burnt in the air to form `CO_(2)`. The number of molecules of `CO_(2)` introduced into ... C. `6.02xx10^(22)` D. `3.01xx10^(22)`
Description : A certain weioght of pure `CaCO_(3)` is made to react completely with 200mL of a HCl solution to given 227mL of `CO_(2)` gas at STP. The notmality of
Last Answer : A certain weioght of pure `CaCO_(3)` is made to react completely with 200mL of a HCl solution to ... at STP. The notmality of the HCl` solution is :