Explore topic-wise MCQs in Chemical Engineering.

This section includes 1154 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1001.

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 reminder going to CO, the Orsat analysis in volume percent is

A. CO2 : 6.26, CO : 1.56, O2 : 3.91, H2O :15.66, N2 : 72.60
B. CO2 : 7.42, CO : 1.86, O2 : 4.64, N2:86.02
C. CO2 : 6.39, CO : 1.60, O2 : 3.99, H2O:25.96, N2:72.06
D. CO2 : 7.60, CO : 1.90, O2 : 4.75, N2 : 85.74
Answer» C. CO2 : 6.39, CO : 1.60, O2 : 3.99, H2O:25.96, N2:72.06
1002.

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
Answer» B. dew point
1003.

Ignition temperature decreases progressively from anthracite to lignite, because

A. volatile matter content increases.
B. carbon content decreases.
C. moisture content increases.
D. ash content increases.
Answer» B. carbon content decreases.
1004.

Which of the following is coking ?

A. Vitrain
B. Fussain
C. both (a) & (b)
D. Neither (a) nor (b)
Answer» B. Fussain
1005.

High temperature in gasification of coal favours

A. high production of CO2.
B. low production of CO2.
C. high production of CO.
D. both (b) and (c).
Answer» E.
1006.

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
1007.

Percentage of nitrogen in blast furnace gas may be around

A. 5
B. 25
C. 55
D. 80
Answer» D. 80
1008.

Which of the following can be made into briquettes without the use of a binder ?

A. lignite
B. Bituminous coal
C. Anthracite coal
D. None of these
Answer» B. Bituminous coal
1009.

Calorific value of

A. light paraffinic fuel oils is equal to that of equivalent olefins.
B. n-paraffin is lower than that of iso-paraffins of the same compounds.
C. light paraffinic fuel oils is higher than that of equivalent olefins.
D. light paraffinic fuel oils is lower than that of equivalent olefins.
Answer» D. light paraffinic fuel oils is lower than that of equivalent olefins.
1010.

Critical Air Blast (CAB) value of coke is a direct measure of its

A. reactivity
B. hardness
C. strength
D. none of these
Answer» B. hardness
1011.

Which of the following has the highest calorific value ?

A. Lignite
B. Sub-bituminous coal
C. Anthracite
D. Peat
Answer» D. Peat
1012.

Presence of free moisture in coal during its high temperature carbonisation

A. reduces the coking time.
B. protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls.
C. increases the loss of fine coal dust from the ovens when charging.
D. none of these.
Answer» C. increases the loss of fine coal dust from the ovens when charging.
1013.

Removal of hydrogen from coke oven gas

A. increases its calorific value.
B. decreases its calorific value.
C. does not alter its calorific value.
D. is not possible on commerical scale.
Answer» B. decreases its calorific value.
1014.

Most of the coking coals are

A. anthracite
B. bituminous
C. lignite
D. none of these
Answer» C. lignite
1015.

A coal gasifier opearating at 20 atm. (e.g. Lugri gasifier) as compared to one operating at atmospheric pressure (e.g. Kopper-Totzek or Winkler gasifier) will produce a gas having

A. higher methane content and thus higher calorific value.
B. higher carbon monoxide content.
C. lower carbon dioxide content.
D. none of these.
Answer» B. higher carbon monoxide content.
1016.

In case of pulverised coal fired steam boiler, the secondary air serves the main purpose of

A. transportation of coal.
B. drying of coal.
C. combustion of coal by supplying it around the burner.
D. preheating the primary air.
Answer» D. preheating the primary air.
1017.

A coal having higher volatile matter content will necessarily have lower

A. ash fusion temperature.
B. calorific value.
C. ignition temperature.
D. caking index.
Answer» D. caking index.
1018.

With increases in carbonisation temperature

A. coke even gas yield increases.
B. tar yield increases.
C. hydrogen percentage in the coke oven gas decreases.
D. methane percentage in the coke oven gas increases.
Answer» B. tar yield increases.
1019.

Fusion point of coal ash increases with increase in its __________ content.

A. iron sulphate
B. iron silicate
C. lime and magnesia
D. all (a), (b) and (c)
Answer» E.
1020.

Which of the following is used for making the explosive 'TNT' ?

A. Benzol
B. Toluene
C. Pyridine
D. Cerosote
Answer» C. Pyridine
1021.

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.
1022.

High ash coals

A. are soft & friable (poor strength and size stability).
B. require longer time of carbonisation as ash offers resistance to heat transfer.
C. produce larger quantity of coke oven gas.
D. none of these.
Answer» C. produce larger quantity of coke oven gas.
1023.

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).
Answer» E.
1024.

Of the total tar present in raw coke oven gas, the tar recovered in primary cooler is about __________ percent.

A. 5
B. 25
C. 55
D. 75
Answer» C. 55
1025.

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.
1026.

Fischer-Tropsch method aims at the

A. gasification of coal.
B. synthesis of gasoline (from water gas).
C. hydrogenation of coal to produce gasoline.
D. none of these.
Answer» C. hydrogenation of coal to produce gasoline.
1027.

Bunsen burner is an example of a/an __________ burner.

A. inside mixing/premix type
B. outside mixing/diffusion flame/nozzle mix type.
C. rotary cup.
D. submerged combustion.
Answer» B. outside mixing/diffusion flame/nozzle mix type.
1028.

Which will have the least volatile matter and hence will be the most difficult to ignite?

A. Bituminous coal
B. Coke
C. Semi-bituminous coal
D. Aanthracite
Answer» C. Semi-bituminous coal
1029.

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
1030.

Preheating of __________ the flame temperature.

A. the gaseous fuel before combustion decreases
B. combustion air decreases
C. either the fuel or the air or both, increases
D. either the fuel or the air does not affect.
Answer» D. either the fuel or the air does not affect.
1031.

Which of the following fertilisers is produced in the by-products recovery (from coke oven gas) plant attached to an integrated steel plant ?

A. Ammonium sulphate
B. Ammonium nitrate
C. Ammonium phosphate
D. None of these
Answer» B. Ammonium nitrate
1032.

In Lurgi coal gasifier,

A. coking coals cannot be used.
B. low carbon conversion efficiency is achieved.
C. entrainment of solids is higher.
D. larger quantity of coal can be processed.
Answer» E.
1033.

Which of the following is not applicable to fluidised bed combustion of coal ?

A. It can not burn low grade coal.
B. It achieves higher fuel combustion efficiency.
C. Less heat transfer surface area is required in boilers.
D. None of these.
Answer» B. It achieves higher fuel combustion efficiency.
1034.

Which of the following is not a by-product recovered in a high temperature coal carbonisation plant ?

A. Benzol
B. Pitch-cresosote mixture (PCM)
C. Napthalene
D. Ethylene
Answer» E.
1035.

Carbon Content by weight in air dried wood may be about __________ percent.

A. 10
B. 25
C. 50
D. 80
Answer» D. 80
1036.

Presence of force moisture in coal is most disadvantageous during its

A. transportation and handling
B. washing
C. pulverisation
D. storage
Answer» D. storage
1037.

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. Liquified petroleum gas
Answer» E.
1038.

Producer gas containing least amount of tar is produced by the

A. partial combustion of coal.
B. partial combustion of large size (< 50 mm) coke.
C. high pressure gasification of coal (e.g. in Lurgi gasifier).
D. atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier).
Answer» C. high pressure gasification of coal (e.g. in Lurgi gasifier).
1039.

"Overfire burning" in a furnace is a phenomenon characterised by the

A. supply of excess fuel.
B. supply of excess air.
C. burning of carbon monoxide and other incombustibles in upper zone of furnace by supplying more air.
D. none of these.
Answer» D. none of these.
1040.

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
Answer» C. Producer gas
1041.

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
1042.

Pulverised coal used in boiler firing need not have

A. less moisture content
B. high fusion point of its ash
C. high bulk density
D. lower ash content
Answer» C. high bulk density
1043.

Low temperature carbonisation of coal takes place at __________ °C.$

A. 300
B. 1100
C. 700
D. 150
Answer» D. 150
1044.

Oxygen required for theoretically complete combustion of 1 Nm3 methane is __________ Nm3.

A. 2
B. 4
C. 6
D. 1
Answer» B. 4
1045.

'Wobbe index' is a characteristic of

A. solid fuels
B. gaseous fuels
C. liquid fuels
D. fat coals
Answer» C. liquid fuels
1046.

Which of the following is the most reactive (as regards the formation of CO + H2 from C + H2O) ?

A. Blast furnace coke
B. Low temperature coke
C. Anthracite coal
D. Sub-bituminous coal
Answer» C. Anthracite coal
1047.

In high temperature carbonisation (as compared to low temperature carbonisation) of coal

A. coke oven gas yield is more.
B. tar yield is less but free carbon in tar is more.
C. calorific value of coke oven gas is less.
D. all (a), (b), and (c).
Answer» E.
1048.

Cannel coal and boghead coal are the examples of

A. humic coals
B. liptobiolites
C. sapropelic coals
D. none of these
Answer» D. none of these
1049.

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).
Answer» E.
1050.

Which of the following is not a manufactured fuel ?

A. Furnace oil
B. Bagasse
C. Semi-coke
D. Kerosene
Answer» C. Semi-coke