MCQOPTIONS
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MCQOPTIONS
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.
| 801. |
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. | |
| 802. |
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 | |
| 803. |
Shatter index of the coke is a measure of its |
| A. | strength |
| B. | bulk density |
| C. | reactivity |
| D. | none of these |
| Answer» B. bulk density | |
| 804. |
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. | |
| 805. |
Nitrogen present in the flue gas is determined in the orsat apparatus by absorbing it in |
| A. | KOH |
| B. | ammoniacal cuprous chloride |
| C. | pyrogallol solution |
| D. | none of these |
| Answer» E. | |
| 806. |
Which of the following fuel gases is heavier than air ? |
| A. | Blast furnace gas |
| B. | Coke oven gas |
| C. | Natural gas |
| D. | Water gas |
| Answer» B. Coke oven gas | |
| 807. |
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. | |
| 808. |
Which of the following gaseous fuels is likely to have the highest gross calorific value? |
| A. | Sewage gas |
| B. | LPG |
| C. | Producer gas |
| D. | Natural gas |
| Answer» C. Producer gas | |
| 809. |
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). |
| Answer» E. | |
| 810. |
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. | |
| 811. |
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. | 43497 |
| C. | 70-100 |
| D. | 150-200 |
| Answer» B. 43497 | |
| 812. |
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 | |
| 813. |
Which of the following has the highest calorific value (kcal/Nm3) ? |
| A. | Carburetted water gas |
| B. | Gobar gas |
| C. | Natural gas |
| D. | LPG |
| Answer» E. | |
| 814. |
Which of the following would require least amount of secondary air for combustion ? |
| A. | Coke breeze containing 25% ash and 2% volatile matter. |
| B. | Anthracite containing 10% volatile matter and 8% ash. |
| C. | Bituminous coal containing 20% ash and 25% volatile matter. |
| D. | Semi-bituminous coal containing 25% ash and 20% volatile matter. |
| Answer» B. Anthracite containing 10% volatile matter and 8% ash. | |
| 815. |
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 |
| Answer» D. Producers' gas | |
| 816. |
Gross heating value of coal is __________ the net heating value. |
| A. | higher than |
| B. | lower than |
| C. | same as |
| D. | either (a) or (b); depends on the type of coal |
| Answer» B. lower than | |
| 817. |
Weathering of coal during storage causes |
| A. | reduction in coal size. |
| B. | increase in its friability. |
| C. | decrease in its caking capacity. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 818. |
Largest constituent of coke oven gas is |
| A. | N2 |
| B. | H2 |
| C. | CH4 |
| D. | CO2 |
| Answer» C. CH4 | |
| 819. |
Caking index of the coal blend used for the manufacture of metallurgical coke should be around |
| A. | 5 |
| B. | 21 |
| C. | 40 |
| D. | 48 |
| Answer» C. 40 | |
| 820. |
Which of the following oil gasification processes is non-catalytic ? |
| A. | Semet-Solvay process |
| B. | Segas process |
| C. | Onia-Gegi process |
| D. | Steam reforming of naphtha |
| Answer» B. Segas process | |
| 821. |
Volatile matter content in coking coal may be about __________ percent. |
| A. | 1 |
| B. | 7 |
| C. | 22 |
| D. | 46 |
| Answer» D. 46 | |
| 822. |
Which of the following is a rich fuel gas ? |
| A. | Producer gas. |
| B. | Coal gas from underground gasification of coal. |
| C. | Refinery gases. |
| D. | None of these. |
| Answer» D. None of these. | |
| 823. |
The hottest part of the flame lies in its____zone. |
| A. | non-luminous |
| B. | luminous |
| C. | yellow |
| D. | unburnt gases |
| Answer» B. luminous | |
| 824. |
The cooling medium used in dry quenching of coke is |
| A. | nitrogen |
| B. | air |
| C. | phenolic water |
| D. | carbon dioxide |
| Answer» B. air | |
| 825. |
Calorific value of bituminous coal may be around __________ Kcal/kg. |
| A. | 500 |
| B. | 1500 |
| C. | 6500 |
| D. | 20000 |
| Answer» D. 20000 | |
| 826. |
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 | |
| 827. |
Out of the following fuels, the difference between the net and gross calorific value is maximum in case of |
| A. | pitch |
| B. | fuel oil |
| C. | blast furnace gas |
| D. | bituminous coal |
| Answer» C. blast furnace gas | |
| 828. |
Method of maintaining fires in furnace during standby periods without undue consumption of fuel is called |
| A. | back draughting. |
| B. | banking. |
| C. | under pressurising. |
| D. | none of these. |
| Answer» C. under pressurising. | |
| 829. |
Coke oven gas burns with an yellowish flame, because of the presence of |
| A. | CO2 |
| B. | CH4 |
| C. | H2 |
| D. | NH3 |
| Answer» C. H2 | |
| 830. |
Optimum preheating temperature for pitch creosote mixture (PCM) which is also termed as C.T.F-200, before atomisation through burners is |
| A. | 200 °F |
| B. | 200 °C |
| C. | 200 °K |
| D. | 200 °R |
| Answer» B. 200 ¬∞C | |
| 831. |
Which of the following is the most important deterrents to an extended use of pulverised coal in boiler firing ? |
| A. | Ash disposal problem. |
| B. | Excessive fly-ash discharge from the stack. |
| C. | High power consumption in its transportation. |
| D. | Erosion of induced draft fan blades. |
| Answer» B. Excessive fly-ash discharge from the stack. | |
| 832. |
The most matured coal out of the following is |
| A. | lignite |
| B. | semi-anthracite |
| C. | sub-bituminous |
| D. | bituminous |
| Answer» C. sub-bituminous | |
| 833. |
Which of the following has the highest heat of combustion? |
| A. | H2 |
| B. | CO |
| C. | CH4 |
| D. | C2H6 |
| Answer» E. | |
| 834. |
For maximum discharge through a chimney, its height should be |
| A. | 200 meters. |
| B. | infinitely long. |
| C. | more than 105.7 metres. |
| D. | equal to the height of the hot gas column producing draught. |
| Answer» E. | |
| 835. |
Sometimes water is sprayed during coal charging in the coke oven, which helps in |
| A. | prevention of clinker formation in the oven. |
| B. | controlling the dust nuisance while charging the coal. |
| C. | reducing the cracking of hydrocarbons in the gas and increasing the percentage of CO & H2 in the gas (due to the endothermic reaction represented by C + H2O = CO + H2) |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 836. |
By-products are __________ recovered in 'Beehive ovens'. |
| A. | fully |
| B. | partially |
| C. | not at all |
| D. | negligibly |
| Answer» D. negligibly | |
| 837. |
A coal containing high amount of volatile matter will have |
| A. | low ignition temperature |
| B. | very little ash content |
| C. | high fusion point of its ash |
| D. | low adiabatic flame temperature |
| Answer» B. very little ash content | |
| 838. |
Ionisation potential applied across the electrodes of electrostatic tar precipitator is around |
| A. | 230 V AC |
| B. | 60 KV AC |
| C. | 230 V DC |
| D. | 60 KV DC |
| Answer» E. | |
| 839. |
Bulk density of pulverised coal may be about __________ kg/m3. |
| A. | 100 |
| B. | 500 |
| C. | 1000 |
| D. | 1500 |
| Answer» C. 1000 | |
| 840. |
Calorific value of of blast furnace gas is around __________ KCal/Nm3. |
| A. | 850 |
| B. | 1800 |
| C. | 4200 |
| D. | 6500 |
| Answer» B. 1800 | |
| 841. |
The calorific value of L.D. converter gas is about __________ Kcal/Nm3 . |
| A. | 1800 |
| B. | 800 |
| C. | 4500 |
| D. | 10000 |
| Answer» B. 800 | |
| 842. |
Use of preheated air for combustion of fuel in the furnace, increases the |
| A. | scale losses of the furnace stock. |
| B. | calorific value of the fuel. |
| C. | flame temperature. |
| D. | none of these. |
| Answer» D. none of these. | |
| 843. |
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. | |
| 844. |
Bomb calorimeter is used for the determination of calorific value of the __________ fuels. |
| A. | gaseous |
| B. | solid |
| C. | liquid |
| D. | both (b) and (c) |
| Answer» E. | |
| 845. |
Fuel consumption in coke making can be reduced by |
| A. | preheating, blending and de-ashing the coal. |
| B. | stamped charging of coal. |
| C. | dry quenching of coke. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 846. |
Rate of low temperature oxidation of coal due to bad storage conditions |
| A. | decreases with increase in surface area. |
| B. | does not vary with increase in surface area. |
| C. | is more for low volatile coal compared to high volatile coal. |
| D. | is accelerated by storage in large heaps with small surface to volume ratio. |
| Answer» E. | |
| 847. |
Benzene is used |
| A. | as a motor fuel. |
| B. | as an explosive. |
| C. | for making insecticides (e.g., DDT, BHC etc.), detergent & rubber (SBR). |
| D. | as a perfume. |
| Answer» D. as a perfume. | |
| 848. |
Compound coke ovens are those which can be heated by |
| A. | both steam and electrical power. |
| B. | lean gas (e.g., B.F. gas). |
| C. | rich gas (e.g., coke oven gas). |
| D. | both (b) and (c). |
| Answer» E. | |
| 849. |
The advantage of firing pulverised coal in the furnace lies in the fact, that it |
| A. | permits the use of high ash content coal. |
| B. | permits the use of low fusion point ash coal. |
| C. | accelerates the burning rate and economises on fuel combustion. |
| D. | all (a), (b) and (c). |
| Answer» D. all (a), (b) and (c). | |
| 850. |
Which adsorbant is used for removing sulphur compounds (S Q, H2S, RSH etc.) removal from coke oven gas in by-products recovery plant ? |
| A. | Silica gel |
| B. | Diatomaceous earth |
| C. | Basalt |
| D. | Bog iron (i.e., moist ferric hydroxide) |
| Answer» E. | |