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.
| 1. |
Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm /ton of dry coal. |
| A. | 60 |
| B. | 160 |
| C. | 500 |
| D. | 750 |
| Answer» C. 500 | |
| 2. |
Which of the following is the most reactive (as regards the formation of CO + H from C + HO) ? |
| A. | Blast furnace coke |
| B. | Low temperature coke |
| C. | Anthracite coal |
| D. | Sub-bituminous coal |
| Answer» C. Anthracite coal | |
| 3. |
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 | |
| 4. |
The gasification reaction represented by, C + HO = CO + H, is |
| A. | exothermic |
| B. | endothermic |
| C. | catalytic |
| D. | autocatalytic |
| Answer» C. catalytic | |
| 5. |
Which of the following will generate maximum volume of product of complete combustion (Nm/Nm of fuel) ? |
| A. | Carburetted water gas |
| B. | Blast furnace gas |
| C. | Natural gas |
| D. | Producers' gas |
| Answer» D. Producers' gas | |
| 6. |
Which of the following will be unsuitable for dust cleaning from flue gas at 400°C from a pulverised coal fired boiler ? |
| A. | Multicyclones |
| B. | Bag filter |
| C. | Wet scrubber |
| D. | Hydrocyclones. |
| Answer» C. Wet scrubber | |
| 7. |
Which of the following has the highest calorific value (kcal/Nm) ? |
| A. | Carburetted water gas |
| B. | Gobar gas |
| C. | Natural gas |
| D. | LPG |
| Answer» E. | |
| 8. |
The calorific value of natural gas is about __________ kcal/Nm. |
| A. | 10, 000 |
| B. | 2500 |
| C. | 25, 000 |
| D. | 35, 000 |
| Answer» B. 2500 | |
| 9. |
Calorific value of coke oven gas is around __________ Kcal/Nm. |
| A. | 900 |
| B. | 4200 |
| C. | 7500 |
| D. | 2000 |
| Answer» C. 7500 | |
| 10. |
Yield of blast furnace gas is about __________ Nm /ton of pig iron. |
| A. | 300 |
| B. | 2000 |
| C. | 5000 |
| D. | 10000 |
| Answer» C. 5000 | |
| 11. |
Coke oven gas is stripped of its HS and mercaptans content by |
| A. | absorption in wash oil. |
| B. | adsorption on bog iron bed. |
| C. | bubbling it through dilute sulphuric acid. |
| D. | adsorption on silica gel. |
| Answer» C. bubbling it through dilute sulphuric acid. | |
| 12. |
Which of the following fuel gases will require maximum amount of air for combustion of 1 Nm gas ? |
| A. | Blast furnace gas |
| B. | Natural gas |
| C. | Producer gas |
| D. | Water gas |
| Answer» C. Producer gas | |
| 13. |
Dust content in raw blast furnace gas is about __________ gm/Nm , hence it is cleaned to the dust level of about < 10 mg /Nm before use. |
| A. | 15-30 |
| B. | 1-2 |
| C. | 70-100 |
| D. | 150-200 |
| Answer» B. 1-2 | |
| 14. |
With increase in the time of carbonisation at a particular temperature (say 1000°C), the __________ percentage in coke oven gas increases. |
| A. | hydrogen |
| B. | methane |
| C. | unsaturated hydrocarbons |
| D. | all (a), (b) and (c) |
| Answer» B. methane | |
| 15. |
Abel apparatus is used for those oils, whose flash points are___°F. |
| A. | <120 |
| B. | >120 |
| C. | >280 |
| D. | 300-600 |
| Answer» B. >120 | |
| 16. |
Oxygen required for theoretically complete combustion of 1 Nm methane is __________ Nm. |
| A. | 2 |
| B. | 4 |
| C. | 6 |
| D. | 1 |
| Answer» B. 4 | |
| 17. |
As the C/H ratio of the fuel increases, the amount of CO formed on combustion __________ for the same percentage of excess air. |
| A. | decreases |
| B. | increases |
| C. | remains same |
| D. | may increase or decrease depending on the type of fuel |
| Answer» C. remains same | |
| 18. |
Which of the following has the least calorific value (kcal/Nm) ? |
| A. | Blast furnace gas |
| B. | Coke oven gas |
| C. | Sewage gas |
| D. | Natural gas |
| Answer» B. Coke oven gas | |
| 19. |
The combustion reaction, C + O = CO, is |
| A. | exothermic |
| B. | endothermic |
| C. | autocatalytic |
| D. | none of these |
| Answer» B. endothermic | |
| 20. |
Volumetric ratio of N to O in dry atmospheric air is |
| A. | 0.21 |
| B. | 3.76 |
| C. | 4.76 |
| D. | 0.79 |
| Answer» C. 4.76 | |
| 21. |
Mineral matter, '' and ash percentage '' in coal are roughly related as |
| A. | = 1.8 |
| B. | = 0.5 |
| C. | = 1.1 |
| D. | = |
| Answer» D. = | |
| 22. |
Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around __________ Nm . |
| A. | 30 |
| B. | 300 |
| C. | 3000 |
| D. | 30, 000 |
| Answer» C. 3000 | |
| 23. |
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 | |
| 24. |
The calorific value of a gas of composition CO = 20%, H = 50%, CH = 30%, is . If the composition of gas is changed to H = 50%, CH = 30%, CO = 10%, N = 10%, then the calorifice value will be |
| A. | 0.95 |
| B. | 1.05 |
| C. | 1.8 |
| Answer» B. 1.05 | |
| 25. |
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/Nm ), 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 | |
| 26. |
Coal is heated in presence of air to a temperature of about __________ °C, while determining its ash content for proximate analysis. |
| A. | 500 |
| B. | 750 |
| C. | 950 |
| D. | 1100 |
| Answer» C. 950 | |
| 27. |
If CO is not fully absorbed by the KOH solution meant for its absorption in the orsat apparatus, it will appear as |
| A. | O |
| B. | CO |
| C. | N |
| D. | SO |
| Answer» E. | |
| 28. |
High temperature carbonisation of coal takes place at __________ °C. |
| A. | 2000 |
| B. | 600 |
| C. | 1100 |
| D. | 1600 |
| Answer» D. 1600 | |
| 29. |
Calorific value of gobar gas (containing CH = 60% , H = 10% ; CO = 30%) may be about __________ Kcal/Nm. |
| A. | 1800 |
| B. | 3200 |
| C. | 5400 |
| D. | 10200 |
| Answer» D. 10200 | |
| 30. |
When steam is passed over coal resulting in the endothermic reaction represent by, C + HO = CO + H, it is called the __________ of coal. |
| A. | carbonisation |
| B. | oxidation |
| C. | coalification |
| D. | gasification |
| Answer» E. | |
| 31. |
Dry air requirement for burning 1 Nm of CO to CO may be around __________ Nm. |
| A. | 2.4 |
| B. | 1.75 |
| C. | 0.87 |
| D. | 11.4 |
| Answer» B. 1.75 | |
| 32. |
Ammonia content in raw coke oven gas is about __________ gm/Nm. |
| A. | 1 |
| B. | 15 |
| C. | 50 |
| D. | 100 |
| Answer» C. 50 | |
| 33. |
Mineral matter content () and ash content () in coal are approximately related as |
| A. | = 1.1 |
| B. | = |
| C. | = 1.5 |
| D. | = 2 |
| Answer» B. = | |
| 34. |
The average molecular weight of a flue gas having the composition by volume as CO = 25%, O = 25%, N = 50% will be |
| A. | 27.6 |
| B. | 23 |
| C. | 47.3 |
| D. | 42.9 |
| Answer» C. 47.3 | |
| 35. |
Which of the following gaseous fuels has the highest net calorific value (kcal/Nm)? |
| A. | Producer gas |
| B. | Carburetted water gas |
| C. | Natural gas |
| D. | Liquified petroleum gas |
| Answer» E. | |
| 36. |
The reaction, C + CO 2CO, taking place during coal gasification is called the __________ reaction. |
| A. | Neumann reversal |
| B. | shift conversion |
| C. | Boudouard |
| D. | reduction |
| Answer» D. reduction | |
| 37. |
The maximum percentage of CO in a flue gas (from a carbonaceous fuel) can be |
| A. | 21 |
| B. | 77 |
| C. | 79 |
| D. | 29 |
| Answer» B. 77 | |
| 38. |
Bulk density of pulverised coal may be about __________ kg/m. |
| A. | 100 |
| B. | 500 |
| C. | 1000 |
| D. | 1500 |
| Answer» C. 1000 | |
| 39. |
C.V. (kcal/Nm) of gaseous fuels __________ with increase in molecular weight. |
| A. | decreases |
| B. | increases |
| C. | remains constant |
| D. | may increase or decrease, depends on combustibles. |
| Answer» E. | |
| 40. |
Which adsorbant is used for removing sulphur compounds (S Q, HS, 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. | |
| 41. |
Temperature of coke oven gas just before entering into saturator (for recovery of NH) is about __________ °C. |
| A. | 30 |
| B. | 65 |
| C. | 120 |
| D. | 180 |
| Answer» C. 120 | |
| 42. |
A carbonaceous fuel (containing no H or hydrocarbons) is burnt and the resulting flue gas contains 21% CO. It means that |
| A. | 21% excess air has been used for combustion. |
| B. | 21% excess oxygen has been used for combustion. |
| C. | complete combustion of fuel has taken place. |
| D. | no excess air has been used for combustion. |
| Answer» D. no excess air has been used for combustion. | |
| 43. |
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 | |
| 44. |
Light oil whose major component is benzol, is obtained by the distillation of crude tar in the temperature range of __________ °C. |
| A. | 80-170 |
| B. | 200-300 |
| C. | 250-270 |
| D. | 280-300 |
| Answer» B. 200-300 | |
| 45. |
The calorific value of 'LPG' (50% propane + 50% butane) is about __________ kcal/Nm. |
| A. | 5000 |
| B. | 25, 000 |
| C. | 10, 000 |
| D. | 15, 000 |
| Answer» C. 10, 000 | |
| 46. |
Gas yield in the Kopper-Totzek coal gasifier is about __________ Nm/ton coal (ash = 35%). |
| A. | 150 |
| B. | 1500 |
| C. | 3500 |
| D. | 5000 |
| Answer» C. 3500 | |
| 47. |
Calorific value of coke even gas produced by low temperature carbonisation of coal is about __________ Kcal/Nm. |
| A. | 4000 |
| B. | 2500 |
| C. | 6500 |
| D. | 10000 |
| Answer» D. 10000 | |
| 48. |
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 | |
| 49. |
Calorific value of of blast furnace gas is around __________ KCal/Nm. |
| A. | 850 |
| B. | 1800 |
| C. | 4200 |
| D. | 6500 |
| Answer» B. 1800 | |
| 50. |
About __________ Nm of air will be required for the complete combustion of 2Nm of CO. |
| A. | 2 |
| B. | 3 |
| C. | 5 |
| D. | 1 |
| Answer» D. 1 | |