MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 408 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 51. |
Use of excess of combustion air in the combustion of fuels results in__________________? |
| A. | Heat losses |
| B. | Long flame |
| C. | Condensation of water vapour from the fuel gas |
| D. | None of these |
| Answer» B. Long flame | |
| 52. |
Undercharging of coal in the by-product coke ovens results in ____________________? |
| A. | Decrease in the c.v. of coke oven gas |
| B. | Increase in its throughput |
| C. | Increase in the c.v. of coke oven gas |
| D. | No change in the c.v. of coke oven gas |
| Answer» B. Increase in its throughput | |
| 53. |
Ultimate analysis of coal determines its _______________ content? |
| A. | Carbon, hydrogen, nitrogen & sulphur |
| B. | Carbon, ash, sulphur & nitrogen |
| C. | Carbon, sulphur, volatile matter & ash |
| D. | Carbon, volatile matter, ash & moisture |
| Answer» B. Carbon, ash, sulphur & nitrogen | |
| 54. |
Turndown ratio of a gas burner is equal to the __________________ ? |
| A. | Maximum to minimum heat input ratio |
| B. | Maximum to minimum permissible gas flow rate |
| C. | Both A. & B. |
| D. | Minimum to maximum heat input ratio |
| Answer» D. Minimum to maximum heat input ratio | |
| 55. |
Traces of tar fog present in the coke oven gas is removed by_________________? |
| A. | Cyclone separator |
| B. | Wet packed scrubber |
| C. | Electrostatic precipitator |
| D. | Washing with monoethanolamine |
| Answer» D. Washing with monoethanolamine | |
| 56. |
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. |
| Answer» E. | |
| 57. |
Tolerable concentration of toxic carbon monoxide in atmospheric air is about ______________ ppm? |
| A. | 50 |
| B. | 1000 |
| C. | 5000 |
| D. | 10000 |
| Answer» B. 1000 | |
| 58. |
To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in___________________? |
| A. | Shallow and small piles |
| B. | Fine sizes without the presence of any lump |
| C. | Closed space without any ventilation facility |
| D. | Large heaps with small surface to volume ratio |
| Answer» B. Fine sizes without the presence of any lump | |
| 59. |
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 |
| Answer» E. | |
| 60. |
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 |
| Answer» D. Is a measure of its caking tendency | |
| 61. |
The temperature at which plastic layer formation takes place during carbonisation of coal varies from ______________ °C ? |
| A. | 100 to 150 |
| B. | 350 to 450 |
| C. | 550 to 650 |
| D. | 700 to 850 |
| Answer» C. 550 to 650 | |
| 62. |
The shift conversion reaction taking place during water gas manufacture is given by__________________? |
| A. | C + H2O ↔ CO + H2 |
| B. | C + 2H2O ↔ CO2 + 2H2 |
| C. | CO + H2O ↔ CO2 + H2 |
| D. | None of these |
| Answer» D. None of these | |
| 63. |
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 |
| D. | O2, CO2, CO |
| Answer» B. CO, O2, CO2 | |
| 64. |
The reaction, C + CO2 ↔ 2CO, taking place during coal gasification is called the ______________ reaction? |
| A. | Neumann reversal |
| B. | Shift conversion |
| C. | Boudouard |
| D. | Reduction |
| Answer» D. Reduction | |
| 65. |
The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always ___________________? |
| A. | 1 |
| B. | < 1 |
| C. | > 1 |
| D. | Unpredictable |
| Answer» D. Unpredictable | |
| 66. |
The ratio of maximum adiabatic flame temperature in air to that in pure oxygen is always___________________? |
| A. | 1 |
| B. | < 1 |
| C. | > 1 |
| D. | Unpredictable |
| Answer» C. > 1 | |
| 67. |
The pyrogallol solution used in Orsat apparatus can absorb_________________? |
| A. | Only O2 |
| B. | Both O2 and CO2 |
| C. | Both O2 and CO |
| D. | All CO, CO2, and O2 |
| Answer» C. Both O2 and CO | |
| 68. |
The optimum percentage of excess air for combustion depends upon the _______________ of the fuel? |
| A. | Type (solid, liquid or gaseous) |
| B. | Calorific value |
| C. | Sulphur content |
| D. | Ignition temperature |
| Answer» B. Calorific value | |
| 69. |
The most matured coal out of the following is__________________? |
| A. | Lignite |
| B. | Semi-anthracite |
| C. | Sub-bituminous |
| D. | Bituminous |
| Answer» C. Sub-bituminous | |
| 70. |
The maximum percentage of CO2 in a flue gas (from a carbonaceous fuel) can be_________________? |
| A. | 21 |
| B. | 77 |
| C. | 79 |
| D. | 29 |
| Answer» B. 77 | |
| 71. |
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 |
| Answer» E. | |
| 72. |
The maximum adiabatic flame temperature in air is _____________ the maximum flame temperature in pure oxygen? |
| A. | Lower than |
| B. | Higher than |
| C. | Same as |
| D. | Not related to |
| Answer» B. Higher than | |
| 73. |
The maximum adiabatic flame temperature in air as compared to that in pure oxygen is_______________? |
| A. | Much lower |
| B. | Much higher |
| C. | Same |
| D. | Either lower or higher, depends on the type of fuel |
| Answer» B. Much higher | |
| 74. |
The main reason for making the copper calorimeter (used in bomb calorimeter) silvery white and shining/polished is to___________________? |
| A. | Minimise its corrosion |
| B. | Avoid radiation heat loss |
| C. | Make it look attractive |
| D. | None of these |
| Answer» C. Make it look attractive | |
| 75. |
The main product of high temperature carbonisation of coal is__________________? |
| A. | Coke |
| B. | Ammonia |
| C. | Tar |
| D. | Coke oven gas |
| Answer» B. Ammonia | |
| 76. |
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 |
| Answer» C. Have proper combustion by supplying it around the burner | |
| 77. |
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 |
| Answer» C. Intermittent and uncontrolled combustion of the fuel | |
| 78. |
The main advantage of forced draft over natural draft is that____________________? |
| A. | Combustion of fuel is complete |
| B. | Smaller height chimney can be used |
| C. | Furnace control is easier |
| D. | All A., B. & C. |
| Answer» E. | |
| 79. |
The lowest temperature, at which a solid fuel produces enough vapors to support continuous combustion, is called ? |
| A. | Fire point |
| B. | Smoke point |
| C. | Burning temperature |
| D. | Kindling temperature |
| Answer» D. Kindling temperature | |
| 80. |
The liquid used for the washing of coal in an industrial coal washery is a mixture of water and ____________________? |
| A. | Carbon tetrachloride |
| B. | Sand (40%) |
| C. | Mineral oil of high viscosity & specific gravity (1.6) |
| D. | None of these |
| Answer» C. Mineral oil of high viscosity & specific gravity (1.6) | |
| 81. |
The internal energy of the combustion products is ____________________ compared to that of reactants? |
| A. | More |
| B. | Less |
| C. | Equal |
| D. | More or less; (depends on the state of fuel.) |
| Answer» C. Equal | |
| 82. |
The hottest part of the flame lies in its _______________ zone? |
| A. | Non-luminous |
| B. | Luminous |
| C. | Yellow |
| D. | Unburnt gases |
| Answer» B. Luminous | |
| 83. |
The heat of combustion of a fuel___________________? |
| A. | Is equal to the heat of formation |
| B. | Is always negative |
| C. | Can’t be known without calculating it |
| D. | Is always positive |
| Answer» C. Can’t be known without calculating it | |
| 84. |
The gasification reaction represented by, C + H2O = CO + H2, is__________________? |
| A. | Exothermic |
| B. | Endothermic |
| C. | Catalytic |
| D. | Autocatalytic |
| Answer» C. Catalytic | |
| 85. |
The gas which contributes maximum to the heating value of natural gas is __________________? |
| A. | CO |
| B. | CO2 |
| C. | H2 |
| D. | CH4 |
| Answer» E. | |
| 86. |
The function of secondary combustion air is to ______________________? |
| A. | Pneumatically convey the pulverised coal |
| B. | Completely burn the volatile matter |
| C. | Burn the lumpy coal |
| D. | None of these |
| Answer» C. Burn the lumpy coal | |
| 87. |
The fuel ratio of a coal is__________________? |
| A. | The ratio of its percentage of fixed carbon to that of volatile matter |
| B. | Helpful in estimation of its rank |
| C. | Both A. and B. |
| D. | Neither A. nor B. |
| Answer» D. Neither A. nor B. | |
| 88. |
The difference between total carbon and fixed carbon of coal will be minimum in case of___________________? |
| A. | Lignite |
| B. | Bituminous coal |
| C. | Anthracite |
| D. | High temperature coke (V.M < 0.5%) |
| Answer» E. | |
| 89. |
The cuprous chloride used in orsat apparatus can absorb___________________? |
| A. | Only CO |
| B. | Both CO and CO |
| C. | Both CO and O2 |
| D. | All CO, CO2, and O2 |
| Answer» E. | |
| 90. |
The cooling medium used in dry quenching of coke is___________________? |
| A. | Nitrogen |
| B. | Air |
| C. | Phenolic water |
| D. | Carbon dioxide |
| Answer» B. Air | |
| 91. |
The combustion reaction, C + O2 = CO2, is ___________________? |
| A. | Exothermic |
| B. | Endothermic |
| C. | Autocatalytic |
| D. | None of these |
| Answer» B. Endothermic | |
| 92. |
The catalyst used in shift converter is _____________________? |
| A. | Nickel |
| B. | Vanadium |
| C. | Silica gel |
| D. | Alumina |
| Answer» B. Vanadium | |
| 93. |
The calorific value of producer gas is around _____________ kcal/Nm3? |
| A. | 1300 |
| B. | 500 |
| C. | 4500 |
| D. | 9000 |
| Answer» B. 500 | |
| 94. |
The calorific value of ‘LPG’ (50% propane + 50% butane) is about ______________ kcal/Nm3? |
| A. | 5000 |
| B. | 25,000 |
| C. | 10,000 |
| D. | 15,000 |
| Answer» C. 10,000 | |
| 95. |
The calorific value of natural gas is about ______________ kcal/Nm3? |
| A. | 10,000 |
| B. | 2,500 |
| C. | 25,000 |
| D. | 35,000 |
| Answer» B. 2,500 | |
| 96. |
The calorific value of L.D. converter gas is about ____________ Kcal/Nm3? |
| A. | 1800 |
| B. | 800 |
| C. | 4500 |
| D. | 10000 |
| Answer» B. 800 | |
| 97. |
The calorific value is the highest out of the following for__________________? |
| A. | Producer gas |
| B. | Water gas |
| C. | Coke oven gas |
| D. | Blast furnace gas |
| Answer» D. Blast furnace gas | |
| 98. |
The calorific value of a gas of composition CO2 = 20%, H2 = 50%, CH4 = 30%, is y. If the composition of gas is changed to H2 = 50%, CH4 = 30%, CO2 = 10%, N2 = 10%, then the calorific value will be___________________? |
| A. | y |
| B. | 0.95 y |
| C. | 1.05 y |
| D. | 1.8 y |
| Answer» B. 0.95 y | |
| 99. |
The bright glow of a combustion process is the characteristic of ______________ temperature oxidation of coal? |
| A. | Fast & high |
| B. | Slow & low |
| C. | Slow & high |
| D. | Fast & slow |
| Answer» B. Slow & low | |
| 100. |
The average molecular weight of a flue gas having the composition by volume as CO2 = 25%, O2 = 25%, N2 = 50% will be___________________? |
| A. | 27.6 |
| B. | 23 |
| C. | 47.3 |
| D. | 42.9 |
| Answer» C. 47.3 | |