⚗️ Chemical Engineering Solved MCQs with Answers

Practice 1920 approved ⚗️ Chemical Engineering questions with verified answers from the 🛠️ Engineering Essentials subject for Pakistan exams.

1920 solved MCQs

Growth of __________ is promoted by the presence of manganese in water.Answer: Micro-organisms Average human body contains about __________ percent water by weight.Answer: 70 Noise level audible to audience sitting in the 5th row from the stage during a large orchestra show corresponds to about __________ decibels.Answer: 135 If carbon monoxide content in atmospheric air exceeds __________ ppm, death is bound to occur.Answer: 3000 (i.e. 0.3%) Skull is not formed on the carbon blocks in the hearth of a blast furnace, when it becomes cold, becaus of itsAnswer: Non-wetting characteristic. Firing temperature of magnesite bricks is about __________ °C.Answer: 1600-1800 Hollow refractory bricks are made byAnswer: Slip casting Quartz isAnswer: All (a), (b) and (c). An indication of degree of firing in silica brick is itsAnswer: Specific gravity Panel test determines the __________ of refractories.Answer: Spalling resistance Fireclay bricks are not used in theAnswer: Bast furnace Fusion point of a basic refractory material isAnswer: Reduced by the addition of acid oxides. RUL of refractories depends on theAnswer: All (a), (b) and (c). Which is the stable form of silica between 1470°C and the melting point 1713°C ?Answer: Cristobalite Resistance to slag attack of a refractoryAnswer: All (a), (b) and (c). GrogAnswer: All (a), (b) and (c). Test piece for determination of RUL of a refractory is heated in a/anAnswer: Electric furnace Magnesite refractories are used for the construction of those furnaces, which areAnswer: Both (b) and (c) Roof of a basic electric furnace is made of __________ bricks.Answer: Silica Capacity of a refractory brick to withstand-sudden changes in temperature is denoted by the property calledAnswer: Spalling resistance. Magnesite bricks are used in those parts of furnaces, which areAnswer: Required to resist corrosive basic slag. Which is not a basic refractory ?Answer: Silicon carbide ThoriaAnswer: All (a), (b) and (c). Which property of refractories is the most important for top section of the blast furnace?Answer: .Resistance to abrasio Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ °C.Answer: 1710 Beryllia (which is used in making crucibles for melting uranium & thorium) is superior to alumina in all respects for high temperature (> 1900°C ) use, exceptAnswer: Cost An insulating refractory brick should have high porosity and low thermal conductivity. Which of the following is not used for inducing porosity in the insulating refractory bricks during its manufacture ?Answer: Sand Firing of refractory brick is done toAnswer: All (a), (b) and (c). Chemically, mullite refractories isAnswer: 3Al₂O₃.2SiO₂ Thermal diffusivity of a refractory brick is high, when its __________ is high.Answer: Thermal conductivity