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.
| 701. |
Assam coals suffers mainly from the disadvantage of high __________ content. |
| A. | ash |
| B. | volatile matter |
| C. | sulphur (4-6%) |
| D. | moisture |
| Answer» D. moisture | |
| 702. |
While the first commercial low temperature coal carbonisation plant is located at Neyveli (in Chennai), the second such plant has been built at |
| A. | Dankuni (West Bengal) |
| B. | Dhanbad |
| C. | Singreni (AP.) |
| D. | Raniganj |
| Answer» B. Dhanbad | |
| 703. |
Nitrogen in coal |
| A. | is present upto 1-2%. |
| B. | comes from protein in parent vegetable matter. |
| C. | is recovered as ammonia during its carbonisation. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 704. |
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. | |
| 705. |
Preheating of a gaseous fuel results in increased |
| A. | flame length |
| B. | flame temperature |
| C. | quantity of flue gas |
| D. | ignition temperature |
| Answer» C. quantity of flue gas | |
| 706. |
C/H ratio is the minimum in case of |
| A. | furnace oil |
| B. | natural gas |
| C. | coal |
| D. | naphtha |
| Answer» C. coal | |
| 707. |
A coal with high __________ content, would ignite most easily. |
| A. | fixed carbon |
| B. | volatile matter |
| C. | ash |
| D. | oxygen |
| Answer» C. ash | |
| 708. |
Coal is pulverised before burning in large capacity boiler furnaces mainly to |
| A. | ensure its complete combustion. |
| B. | facilitate easy ash removal. |
| C. | enhance its calorific value. |
| D. | provide trouble free operation. |
| Answer» B. facilitate easy ash removal. | |
| 709. |
Preheating of combustion air is done to |
| A. | increase the adiabatic flame temperature. |
| B. | increase the calorific value of the fuel. |
| C. | complete the combustion of fuel. |
| D. | reduce its requirement for effecting the complete combustion. |
| Answer» B. increase the calorific value of the fuel. | |
| 710. |
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. | |
| 711. |
Water gas constitutes mainly of |
| A. | CO & H2 |
| B. | CO & N2 |
| C. | CO2 & H2 |
| D. | CH4 & H2 |
| Answer» B. CO & N2 | |
| 712. |
Coal tar (produced by high temperature carbonisation) is the main source of |
| A. | aromatic compounds |
| B. | alphatic compounds |
| C. | paraffins |
| D. | olefins |
| Answer» B. alphatic compounds | |
| 713. |
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 | |
| 714. |
__________ prohibits the use of alcohols directly in petrol engines. |
| A. | Low octane number |
| B. | High cost & availability |
| C. | Low flash point |
| D. | Low calorific value |
| Answer» C. Low flash point | |
| 715. |
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) | |
| 716. |
Coal is heated in absence of air for 7 minutes at a temperature of about __________ °C, during its volatile matter determination for proximate analysis.$ |
| A. | 550 |
| B. | 750 |
| C. | 950 |
| D. | 1150 |
| Answer» D. 1150 | |
| 717. |
Abel apparatus is used for those oils, whose flash points are___°F.$ |
| A. | <120 |
| B. | >120 |
| C. | >280 |
| D. | 300-600 |
| Answer» B. >120 | |
| 718. |
Net calorific value is the gross calorific value less the __________ heat of water in the product of combustion when cooled to 15°C.$ |
| A. | sensible |
| B. | latent |
| C. | sensible and latent |
| D. | none of these |
| Answer» D. none of these | |
| 719. |
Yield of charcoal in high temperature carbonisation of wood is about __________ percent. |
| A. | 10 |
| B. | 25 |
| C. | 50 |
| D. | 75 |
| Answer» C. 50 | |
| 720. |
__________ has the widest inflammability limit (explosion limit) of all the gases. |
| A. | Hydrogen |
| B. | Carbon monoxide |
| C. | Acetylene |
| D. | Methane |
| Answer» D. Methane | |
| 721. |
Percentage of methane in coke oven gas may be around |
| A. | 5 |
| B. | 15 |
| C. | 25 |
| D. | 50 |
| Answer» D. 50 | |
| 722. |
High pressure coal gasification is employed in __________ process. |
| A. | Lurgi |
| B. | Kopper-Totzek |
| C. | Winkler |
| D. | none of these |
| Answer» B. Kopper-Totzek | |
| 723. |
Calorific value of dry wood may be around __________ Kcal/kg. |
| A. | 5 |
| B. | 50 |
| C. | 500 |
| D. | 5000 |
| Answer» B. 50 | |
| 724. |
Fossil fuels mean |
| A. | solid fuels |
| B. | liquid fuels |
| C. | those fuels which are found in the crust of earth. |
| D. | premature fuels with low calorific value. |
| Answer» D. premature fuels with low calorific value. | |
| 725. |
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. | |
| 726. |
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 | |
| 727. |
Low temperature oxidation of coal is accelerated by the |
| A. | storage in large heaps. |
| B. | storage in compressed piles. |
| C. | absence of porous or friable particles. |
| D. | all (a), (b) and (c). |
| Answer» B. storage in compressed piles. | |
| 728. |
A fuel with high heat release rate will |
| A. | require smaller combustion chamber. |
| B. | have high calorific value. |
| C. | have high adiabatic flame temperature. |
| D. | none of these. |
| Answer» B. have high calorific value. | |
| 729. |
Coking time in narrow by-product coke ovens is around __________ hours. |
| A. | 18 |
| B. | 48 |
| C. | 8 |
| D. | 80 |
| Answer» B. 48 | |
| 730. |
For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3 ), while the C.V. is same on weight basis (i.e., kcal/kg) ? |
| A. | Propane and acetylene |
| B. | Propane and LPG |
| C. | Sewage gas and gobar gas |
| D. | B.F. gas and coke oven gas |
| Answer» B. Propane and LPG | |
| 731. |
Efficiency of the combustion of a fuel is judged by the __________ the flue gas. |
| A. | %of CO2 in |
| B. | % of O2in |
| C. | temperature of |
| D. | colour of |
| Answer» C. temperature of | |
| 732. |
Furnace oil consumption in a furnace for a given duty employing preheated combination air (at 300° ) may be reduced by about __________ percent as compared to the use of atmospheric combustion air.$ |
| A. | 5 |
| B. | 10 |
| C. | 20 |
| D. | 35 |
| Answer» D. 35 | |
| 733. |
Deficiency of combustion air during combustion of a gaseous fuel |
| A. | lengthens the flame. |
| B. | causes heat loss of fuel by its partial combustion. |
| C. | both (a) & (b). |
| D. | shortens the flame. |
| Answer» D. shortens the flame. | |
| 734. |
A good metallurgical coke |
| A. | should have high porosity. |
| B. | should be brittle. |
| C. | must contain moderate quantities of ash, moisture, sulphur and volatile matters. |
| D. | should have low fusion point of its ash. |
| Answer» B. should be brittle. | |
| 735. |
A sooty flame can be made non-luminous by |
| A. | admitting more gas. |
| B. | shutting gas supply. |
| C. | admitting more air. |
| D. | shutting air supply. |
| Answer» D. shutting air supply. | |
| 736. |
Which of the following has the highest theoretical flame temperature ? |
| A. | Blast furnace gas |
| B. | Hydrogen |
| C. | Acetylene |
| D. | Coke oven gas |
| Answer» D. Coke oven gas | |
| 737. |
Which of the following is not endothermic? |
| A. | Cracking |
| B. | Reforming |
| C. | Gasification |
| D. | Partial oxidation |
| Answer» E. | |
| 738. |
Which of the following accounts for maximum energy loss in a boiler ? |
| A. | Flue gases. |
| B. | Ash content in the fuel. |
| C. | Incomplete combustion. |
| D. | Unburnt carbon in flue gases. |
| Answer» B. Ash content in the fuel. | |
| 739. |
Fusion point of coal ash generally varies from 1000 to 1700° C. Ash having fusion point less than __________ °C is liable to form clinker.$ |
| A. | 1100 |
| B. | 1250 |
| C. | 1350 |
| D. | 1400 |
| Answer» B. 1250 | |
| 740. |
Calorific value of gobar gas (containing CH4 = 60% , H2 = 10% ; CO2 = 30%) may be about __________ Kcal/Nm3. |
| A. | 1800 |
| B. | 3200 |
| C. | 5400 |
| D. | 10200 |
| Answer» D. 10200 | |
| 741. |
Which is the heaviest fuel gas out of the following ? |
| A. | Blast furnace gas |
| B. | Coke oven gas |
| C. | Water gas |
| D. | Carburetted water gas |
| Answer» B. Coke oven gas | |
| 742. |
Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier. |
| A. | entrained |
| B. | moving |
| C. | fixed |
| D. | fluidised |
| Answer» B. moving | |
| 743. |
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. | |
| 744. |
Hardgrove grindability index of four coal samples are given below. Which of them is the easiest to grind ? |
| A. | 50 |
| B. | 70 |
| C. | 85 |
| D. | 100 |
| Answer» E. | |
| 745. |
A coal that softens and fuses on heating is |
| A. | classified |
| B. | carbonised |
| C. | caking |
| D. | non-caking |
| Answer» D. non-caking | |
| 746. |
Blast furnace gas compared to coke oven gas has |
| A. | lower ignition temperature. |
| B. | narrower limit of inflammability. |
| C. | higher calorific value. |
| D. | lower theoretical flame temperature. |
| Answer» E. | |
| 747. |
Wood charcoal is obtained by the destructive distillation of wood. It is used in the production of activated carbon, which is not used for the |
| A. | decolourisation of sugar. |
| B. | solvent recovery from air and gases |
| C. | absorption of gases and vapor. |
| D. | electrode manufacture. |
| Answer» E. | |
| 748. |
Number of macrocomponents present in coal according to Stopes are |
| A. | four |
| B. | five |
| C. | six |
| D. | two |
| Answer» B. five | |
| 749. |
Coke having higher porosity has |
| A. | lower bulk density. |
| B. | lower strength. |
| C. | higher reactivity. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 750. |
Higher fuel combustion efficiency can not 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. | |