Explore topic-wise MCQs in Chemical Engineering.

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.

201.

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
Answer» D. Yield of tar is about 3% of dry coal
202.

In low temperature carbonisation of coal as compared to high temperature carbonisation _____________ produced is less?

A. Difference in gross & net calorific value of the coke oven gas
B. Free carbon content in tar
C. Yield percentage of coke
D. Yield of ammonia present in coke oven gas
Answer» B. Free carbon content in tar
203.

In low temperature carbonisation (as compared to high temperature carbonisation) of coal__________________?

A. Ammonia yield is more
B. Aliphatic tar is produced
C. Free carbon in tar is more
D. All A., B. and C.
Answer» C. Free carbon in tar is more
204.

In high temperature carbonisation of coal compared to low temperature carbonisation ?

A. Yield of ammonia is less
B. Aromatic content of tar is low
C. H2 content in the coke oven gas is more
D. Calorific value of the coke oven gas is lower
Answer» D. Calorific value of the coke oven gas is lower
205.

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.
206.

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

A. Gas yield is less
B. Tar yield is more
C. Ignition temperature of coke produced is less
D. Aromatic content of tar produced is more
Answer» E.
207.

In general, the limit of inflammability/explosion limit of fuel gases is widened by the__________________?

A. Increase in gas pressure
B. Increase in temperature (i.e. preheating)
C. Use of pure oxygen for combustion instead of air
D. All A., B. & C.
Answer» E.
208.

In flue gas analysis by Orsat’s apparatus, oxygen is absorbed by____________________?

A. Potassium hydroxide
B. Cuprous chloride
C. Alkaline pyrogallol solution
D. None of these
Answer» D. None of these
209.

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
Answer» B. Potassium hydroxide
210.

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
Answer» B. Dilute potassium carbonate
211.

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
212.

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
Answer» D. Calorific value
213.

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
214.

Ignition temperature of a fuel in air is ______________ that in pure oxygen?

A. More than
B. Less than
C. Equal to
D. Either more or less; depends on the type of fuel
Answer» B. Less than
215.

If the specific heat of gaseous products of combustion of a fuel is high, the abiabatic flame temperature will be_____________?

A. Low
B. High
C. Very high, if the fuel is of low calorific value
D. None of these
Answer» B. High
216.

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
Answer» C. Moisture loss
217.

If CO2 is not fully absorbed by the KOH solution meant for its absorption in the orsat apparatus, it will appear as___________________?

A. O2
B. CO
C. N2
D. SO2
Answer» E.
218.

Highly reactive coke have lower ___________________?

A. Porosity
B. Coke reactivity index (CRI)
C. Critical air blast (CAB) value
D. Both B. and C.
Answer» D. Both B. and C.
219.

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.
220.

Higher percentage of ash in coal meant for the production of metallurgical grade coke ___________________?

A. Decreases the hardness of coke
B. Decreases the abrasion resistance of coke
C. Causes brittleness in steel
D. None of these
Answer» E.
221.

Higher fuel combustion efficiency cannot be achieved by_________________?

A. Preheating of fuel gases & combustion air
B. Reducing sulphur content in the fuel
C. Adopting proper fuel firing technique & fuel preparation
D. Supplying correct amount of combustion air
Answer» C. Adopting proper fuel firing technique & fuel preparation
222.

Higher efficiency in the combustion of solid fuel cannot be achieved by________________?

A. Proper fuel preparation
B. Keeping the flue gas exhaust temperature very high
C. Adopting efficient-fuel firing technique & equipment
D. Supplying correct quantity of combustion air
Answer» C. Adopting efficient-fuel firing technique & equipment
223.

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.
224.

High temperature carbonisation of coal takes place at _______________ °C?

A. 2000
B. 600
C. 1100
D. 1600
Answer» D. 1600
225.

High temperature carbonisation of coal produces__________________?

A. Inferior coke compared to low temperature carbonisation
B. Less of gases compared to liquid products
C. Large quantity of tar compared to low temperature carbonisation
D. None of these
Answer» E.
226.

High sulphur content in a fuel ______________ of the flue gases?

A. Decreases the dew point
B. Increases the dew point
C. Reduces the combustion efficiency by limiting the permissible temperature reduction
D. Both B. and C.
Answer» E.
227.

High rate of heating of coke ovens____________________?

A. May damage its walls due to abrupt excessive swelling of coal
B. Produces larger size coke
C. Increases the time of carbonisation
D. None of these
Answer» B. Produces larger size coke
228.

High pressure coal gasification is employed in ________________ process?

A. Lurgi
B. Kopper-Totzek
C. Winkler
D. None of these
Answer» B. Kopper-Totzek
229.

High excess air in combustion of fuels results in____________________?

A. Increased fuel consumption
B. Incomplete combustion
C. Smoky flame
D. None of these
Answer» B. Incomplete combustion
230.

High ash containing coke____________________?

A. Produces more slag when used in the blast furnace
B. Has poor strength and abrasion resistance
C. Is desirable in producer gas manufacture
D. None of these
Answer» B. Has poor strength and abrasion resistance
231.

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
232.

High amount of sulphur and phosphorous in coke causes ____________________ ?

A. Decrease in its calorific value
B. Increase in its strength
C. Brittleness of steel made by using it
D. None of these
Answer» D. None of these
233.

Height of coke oven is limited (say maximum upto 7 metres) mainly by the_____________________?

A. Problem of uniform heating along its height
B. Structural strength of silica bricks
C. Problem in door cleaning
D. Buckling of ram of pusher car at the time of coke pushing
Answer» B. Structural strength of silica bricks
234.

Heat penetration rate in narrow coke ovens in high temperature carbonisation of coal is around ______________ cm/hr?

A. 2.5
B. 0.5
C. 10
D. 20
Answer» B. 0.5
235.

_____________ has the widest inflammability limit (explosion limit) of all the gases?

A. Hydrogen
B. Carbon monoxide
C. Acetylene
D. Methane
Answer» D. Methane
236.

Hard pitch is used for making_____________________?

A. Pulverised fuel
B. Perfumes
C. Insecticides
D. Plastics
Answer» B. Perfumes
237.

Hard coke is manufactured from___________________?

A. Lignite
B. Bituminous coal
C. Semi-anthracite
D. Anthracite
Answer» C. Semi-anthracite
238.

Gross & net calorific value is the same for___________________?

A. Blast furnace gas
B. Coke oven gas
C. L.D. converter gas
D. None of these
Answer» D. None of these
239.

Gross heating value of coal is ______________ the net heating value?

A. Higher than
B. Lower than
C. Same as
D. None of these
Answer» B. Lower than
240.

Gross calorific value will be equal to the net calorific value for __________________?

A. H2
B. C2H2
C. CO
D. C2H6
Answer» D. C2H6
241.

Gross and net calorific value of a fuel will be the same__________________?

A. If its ash content is zero
B. If its carbon content is very low
C. If its hydrogen/hydrogen compound content is zero
D. Under no circumstances
Answer» D. Under no circumstances
242.

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
Answer» D. Power consumption in grinding the coal will be very high
243.

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
Answer» B. Abradability
244.

Gobar gas is produced by the _______________ of ‘gobar’ (cow dung) ?

A. Hydrolysis
B. Fermentation
C. Oxidation
D. Dehydration
Answer» C. Oxidation
245.

Gobar gas is produced by the ______________ of cow dung?

A. Fermentation
B. Oxidation
C. Hydrogenation
D. None of these
Answer» B. Oxidation
246.

Gobar gas constitutes mainly of___________________?

A. CH4 & CO2
B. CO & CO2
C. CH4 & N2
D. CO & N2
Answer» B. CO & CO2
247.

Gasification of the solid fuel converts its organic part into combustible by interaction with air/oxygen and steam so as to obtain a secondary gaseous fuel of high calorific value having no ash. Gasification reactions are normally carried out at about _____________ °C?

A. 400-500
B. 900-1000
C. 1400-1500
D. 1700-1800
Answer» C. 1400-1500
248.

Gas yield in the Kopper-Totzek coal gasifier is about ______________ Nm3/ton coal (ash = 35%)?

A. 150
B. 1500
C. 3500
D. 5000
Answer» C. 3500
249.

Fussain _____________________?

A. Is friable, charcoal like substance
B. Has highest fixed carbon and lowest volatile matter content of all the four banded components of coal
C. Is non-coking, but when blended with highly coking coal, controls its swelling and produces high strength coke on carbonisation
D. All A., B. and C.
Answer» E.
250.

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.