MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 568 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. |
Which is the stable form of silica upto 1470°C ? |
| A. | Quartz |
| B. | Cristobalite |
| C. | Tridymite |
| D. | None of these |
| Answer» D. None of these | |
| 2. |
Cold crushing strength of fireclay bricks is about __________ kgf/cm. |
| A. | 50-100 |
| B. | 100-150 |
| C. | 200-400 |
| D. | 500-1000 |
| Answer» D. 500-1000 | |
| 3. |
Refractoriness under load (RUL) of fireclay bricks (under a load of 2 kg/cm ) is __________ °C. |
| A. | 500 |
| B. | 1000 |
| C. | >1350 |
| D. | >2000 |
| Answer» D. >2000 | |
| 4. |
SiO percentage in firebrick is about |
| A. | 35-40 |
| B. | 55-60 |
| C. | 80-85 |
| D. | >94 |
| Answer» C. 80-85 | |
| 5. |
Highest melting (m.p = 3070°C) oxide refractory is |
| A. | alumina |
| B. | thoria |
| C. | zirconia |
| D. | magnesia |
| Answer» C. zirconia | |
| 6. |
Which one contains minimum percentage of SiO? |
| A. | Firebrick |
| B. | Sillimanite |
| C. | Semi-silica |
| D. | Aluminous firebrick |
| Answer» C. Semi-silica | |
| 7. |
Silliminite (AlO.SiO) refractory, which is a neutral refractory, is not used in |
| A. | pottery furnace |
| B. | glass melting furnace |
| C. | crucibles |
| D. | gas retorts |
| Answer» E. | |
| 8. |
Fusion temperature of pure silica (SiO) is __________ °C. |
| A. | 1350 |
| B. | 1715 |
| C. | 2570 |
| D. | 2800 |
| Answer» C. 2570 | |
| 9. |
Because of its very high refractoriness of the order of __________ °C, silicon carbide refractories are used in zinc smelting furnace, muffle furnace and for supporting the wares in tunnel kilns. |
| A. | 1800 |
| B. | 2200 |
| C. | 2400 |
| D. | 2700 |
| Answer» E. | |
| 10. |
Machine moulding of dry mixture of refractories requires a pressure of the order of __________ kg/cm. |
| A. | 10 |
| B. | 100 |
| C. | 500 |
| D. | 1000 |
| Answer» E. | |
| 11. |
Cold crushing strength of ordinary fireclay brick is about 950 kg/cm . On exposure to a temperature of about 1500°C, its crushing strength may come down to as low as __________ kg/cm . |
| A. | 450 |
| B. | 250 |
| C. | 150 |
| D. | 65 |
| Answer» E. | |
| 12. |
Which one contains maximum percentage of AlO ? |
| A. | Firebrick |
| B. | Sillimanite |
| C. | Magnesite |
| D. | Aluminous firebrick |
| Answer» C. Magnesite | |
| 13. |
Silica bricks have low spalling resistance below 600°C, due to its |
| A. | very high thermal conductivity. |
| B. | high co-efficient of expansion upto this temperature. |
| C. | high thermal diffusivity. |
| D. | low refractoriness. |
| Answer» C. high thermal diffusivity. | |
| 14. |
Firing temperature of magnesite bricks is about __________ °C. |
| A. | 800-1000 |
| B. | 1000-1200 |
| C. | 1600-1800 |
| D. | 2400-2600 |
| Answer» D. 2400-2600 | |
| 15. |
Firing temperature is minimum (1250-1400 °C) for __________ bricks. |
| A. | fireclay |
| B. | direct bonded basic |
| C. | silica |
| D. | magnesite |
| Answer» B. direct bonded basic | |
| 16. |
Refractoriness/fusion points of 'superduty' refractories is __________ °C. |
| A. | 1520-1630 |
| B. | 1630-1670 |
| C. | > 1730 |
| D. | > 2000 |
| Answer» D. > 2000 | |
| 17. |
Spalling of silica bricks occurs due to abrupt volume changes, when it is cooled below a temperature of __________ °C. |
| A. | 770 |
| B. | 570 |
| C. | 270 |
| D. | 70 |
| Answer» D. 70 | |
| 18. |
Pyrometric cone equivalent (PCE) value (Segar cone) of 'superduty refractories' is more than 33 which corresponds to a temperature of __________ °C. |
| A. | 1520 |
| B. | 1630 |
| C. | 1670 |
| D. | 1730 |
| Answer» E. | |
| 19. |
Which is the stable form of silica below 870°C ? |
| A. | Tridymite |
| B. | Cristobalite |
| C. | Quartz |
| D. | None of these |
| Answer» D. None of these | |
| 20. |
Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ °C. |
| A. | 1380 |
| B. | 1520 |
| C. | 1710 |
| D. | 1915 |
| Answer» D. 1915 | |
| 21. |
Beryllia (which is used in making crucibles for melting uranium & thorium) is superior to alumina in all respects for high temperature (> 1900°C ) use, except |
| A. | cost |
| B. | electrical conductivity |
| C. | thermal conductivity |
| D. | fusion point |
| Answer» B. electrical conductivity | |
| 22. |
Which is the stable form of silica between 1470°C and the melting point 1713°C ? |
| A. | Cristobalite |
| B. | Tridymite |
| C. | Quartz |
| D. | None of these |
| Answer» B. Tridymite | |
| 23. |
Refractoriness under load (RUL) of fireclay bricks (under a load of 2 kg/cm2 ) is __________ °C. |
| A. | 500 |
| B. | 1000 |
| C. | >1350 |
| D. | >2000 |
| Answer» D. >2000 | |
| 24. |
Fusion temperature of pure silica (SiO2) is __________ °C. |
| A. | 1350 |
| B. | 1715 |
| C. | 2570 |
| D. | 2800 |
| Answer» C. 2570 | |
| 25. |
Skull is not formed on the carbon blocks in the hearth of a blast furnace, when it becomes cold, becaus of its |
| A. | on-wetting characteristic |
| B. | igh thermal conductivity |
| C. | igh crushing strength |
| D. | one of these |
| Answer» B. igh thermal conductivity | |
| 26. |
Which property is important for bricks used in the combustion chamber & dome of blast furnace stoves? |
| A. | igh refractoriness |
| B. | igh resistance to spalling |
| C. | igh strength and density |
| D. | ll of the above |
| Answer» B. igh resistance to spalling | |
| 27. |
Which of the following consumes the maximum tonnage of refractories annually in an integrated steel plant? |
| A. | oaking pits |
| B. | eheating furnace |
| C. | .D. converter |
| D. | otary lime kiln |
| Answer» D. otary lime kiln | |
| 28. |
Tyres are made by |
| A. | injection moulding |
| B. | extrusion |
| C. | rotational moulding |
| D. | compression moulding |
| Answer» D. compression moulding | |
| 29. |
Melamine formaldehyde resin which has a very high anti tacking properties, is not used for the |
| A. | electrical insulation purpose. |
| B. | tanning of leather. |
| C. | strengthening of plaster of paris. |
| D. | decorative laminates. |
| Answer» D. decorative laminates. | |
| 30. |
__________ fibres are made of polyamides. |
| A. | Dacron |
| B. | Nylon |
| C. | Rayon |
| D. | Orion |
| Answer» C. Rayon | |
| 31. |
Lavatory cisterns are normally made of |
| A. | expanded polystyrene |
| B. | saturated polyester |
| C. | perspex |
| D. | PVC |
| Answer» B. saturated polyester | |
| 32. |
Poly Vinyl chloride (PVC) is a __________ material. |
| A. | thermoplastic |
| B. | thermosetting |
| C. | fibrous |
| D. | chemically active |
| Answer» B. thermosetting | |
| 33. |
Vinyl flooring is done using __________ sheets. |
| A. | polypropylene |
| B. | PVC |
| C. | polythene |
| D. | polyvinyl acetate |
| Answer» C. polythene | |
| 34. |
Transistor parts and refrigerator components are normally made of |
| A. | polystyrene |
| B. | polyester |
| C. | high density polythene |
| D. | polyurathane |
| Answer» B. polyester | |
| 35. |
Polyvinyl chloride (PVC) |
| A. | is produced by polycondensation reaction. |
| B. | uses either emulsion or suspension polymerisation methods. |
| C. | can be made thermosetting by adding a plasticiser. |
| D. | softening temperature is 200°C. |
| Answer» C. can be made thermosetting by adding a plasticiser. | |
| 36. |
Polypropylene is preferred to polythene, because the former is |
| A. | non-inflammable |
| B. | harder |
| C. | stronger |
| D. | both (b) & (c) |
| Answer» E. | |
| 37. |
Hot drink (e.g, tea) cups are usually made of |
| A. | polystyrene |
| B. | polythene |
| C. | polypropylene |
| D. | PVC |
| Answer» B. polythene | |
| 38. |
Flexible foam (for mattresses) are usually made of |
| A. | PVC |
| B. | silicone rubber |
| C. | polyurethanes |
| D. | polyamides |
| Answer» D. polyamides | |
| 39. |
Condensation of bisphenol A with phosgene produces __________ which possess very good heat resistance. |
| A. | polyurathane |
| B. | polysulphone |
| C. | polycarbonate |
| D. | polyester |
| Answer» D. polyester | |
| 40. |
Phthalic anhydride is used |
| A. | in making PVC |
| B. | as plasticisers |
| C. | in insecticides manufacture |
| D. | for making nylon-6 |
| Answer» C. in insecticides manufacture | |
| 41. |
Low pressure Zeigler process of polythene manufacture |
| A. | employs a pressure of 30 kgf/cm². |
| B. | achieves an yield of 95-98% based on ethylene. |
| C. | produces very low density polythene. |
| D. | does not use any catalyst for polymerisation. |
| Answer» C. produces very low density polythene. | |
| 42. |
__________ resins are produced by the condensation polymerisation of formaldehyde with urea or melamine. |
| A. | Epoxy |
| B. | Amino |
| C. | Alkyd |
| D. | Phenolic |
| Answer» C. Alkyd | |
| 43. |
__________ is produced by polymerisation of chloroprene. |
| A. | Thiokol (a polysulphide rubber) |
| B. | Butyl rubber |
| C. | Neoprene |
| D. | Polyurathane rubber |
| Answer» D. Polyurathane rubber | |
| 44. |
Which of the following rubbers has the widest service temperature range (-75 to 275°C) ? |
| A. | Butyl rubber |
| B. | Silicon rubber |
| C. | Nitrile rubber |
| D. | Silicone rubber |
| Answer» E. | |
| 45. |
Acrilan fibres used for making cloth, carpet & blankets, which is a hard, horny & high melting polymeric material is nothing but |
| A. | polyacrylonitrile |
| B. | polyamide |
| C. | saturated polyester |
| D. | alkyd resin |
| Answer» B. polyamide | |
| 46. |
Polycaprolactum is |
| A. | nylon-6 |
| B. | nylon-66 |
| C. | dacron |
| D. | rayon |
| Answer» B. nylon-66 | |
| 47. |
Density of high density polythene is about __________ gm/c.c. |
| A. | 1.18 |
| B. | 1.05 |
| C. | 0.95 |
| D. | 0.99 |
| Answer» D. 0.99 | |
| 48. |
Which of the following polymers does not belong to the class of polyacrylate polymer ? |
| A. | PMMA |
| B. | Polyacrylonitrile |
| C. | Polyethyl acrylate |
| D. | None of these |
| Answer» E. | |
| 49. |
The repeating units of PTFE are |
| A. | Cl₂CH-CH₃ |
| B. | F₂C = CF₂ |
| C. | F₃C-CF₃ |
| D. | FClC = CF₂ |
| Answer» C. F₃C-CF₃ | |
| 50. |
Which of the following polymers shows the highest anti-tacking properties ? |
| A. | Melamine formaldehyde resin |
| B. | Phenolic resin |
| C. | Epoxy resin |
| D. | Alkyd resin |
| Answer» B. Phenolic resin | |