⚗️ 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

High porosity refractory bricks haveAnswer: All (a), (b) and (c). Vacuum steel degassing units are lined withAnswer: High alumina bricks Pyrometric cone equivalent (PCE) value (Segar cone) of 'superduty refractories' is more than 33 which corresponds to a temperature of __________ °C.Answer: 1730 Which is the stable form of silica below 870°C ?Answer: Quartz Which one expands on heating ?Answer: Silica bricks Refractoriness/fusion points of 'superduty' refractories is __________ °C.Answer: > 1730 Outer combustion chamber of blast furnace stove is lined with __________ bricks.Answer: Fireclay Presence of MgO in alumino-silicate refractories __________ its refractoriness.Answer: Lowers Spalling of silica bricks occurs due to abrupt volume changes, when it is cooled below a temperature of __________ °C.Answer: 270 Walls, roofs & combustion chambers of annealing furnaces are made of __________ bricks.Answer: High duty fireclay Fireclay bricks are used in theAnswer: All (a), (b) and (c). Water content in ground refractory material to be shaped into bricks by hand moulding is about __________ percent.Answer: 20 Chromite refractoriesAnswer: All (a), (b) and (c). Firing temperature is minimum (1250-1400 °C) for __________ bricks.Answer: Fireclay With increase in the alumina content, the refractoriness of high alumina refractoriesAnswer: Increases A steel member used in the furnace construction to take the thrust of the brickwork is calledAnswer: Buckstay With increase in the porosity, thermal spalling resistance of fireclay brickAnswer: Increases Thoria is an expensive refractory material and is radioactive in nature. Thorium oxide is used in the manufacture ofAnswer: Crucibles used for melting of high purity metals.crucibles used for melting of high purity metals. Maximum alumina content in high alumina refractory can be as high as __________ percent.Answer: 90 Refractories are dried in theAnswer: Tunnel kilns Hot metal runner in blast furnace are lined with __________ bricks.Answer: Fireclay Spray test determines the __________ of refractories.Answer: Resistance to slag penetration The linear thermal expansion of __________ bricks upto 1000 °C is very low of the order of ≤ 0.5 percent.Answer: Fireclay Fusion point of an acidic refractory material isAnswer: Reduced by the addition of basic oxides. Which is required in an insulating refractory ?Answer: Neither (a) nor (b) 'Super refractories' are made from pureAnswer: Oxides Chromite refractories areAnswer: Neutral refractory. Which is the most stable crystalline form of silica at room temperature ?Answer: Quartz Silica refractoriesAnswer: Crack when subjected to sudden change of temperature. PCE value (Segar cone) of superduty refractories is more than 33, which is equivalent to a temperature of __________ °C.Answer: 1730