⚗️ 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

Cold chiesel's hammers are made ofAnswer: High carbon steel Carbon refractoriesAnswer: Are not attacked by slags, as they are not wetted by melts. In the X-ray radiography technique, the tube voltage for thicker plates as compared to thin plates, should beAnswer: Higher, as it gives shorter wavelength. Atomic __________ is a whole number for an element.Answer: Number Magnesite refractories have low resistance toAnswer: Both (b) and (c). Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________ kJ.Answer: +4000 Highest cutting speed is achieved by the __________ tool material.Answer: Carbide Which property is important for bricks used in the combustion chamber & dome of blast furnace stoves ?Answer: High refractoriness. The function of neutral flux used in the pyrometallurgy of metal extraction is to increase the __________ of the slag.Answer: Fluidity The maximum linear expansion of silica bricks during firing is about __________ percent.Answer: 3.5 The thermodynamic law, PVy = constant, is not followed by theAnswer: Free expansion of an ideal gas. Pick out the wrong statement about the machinability of metals. Machinability of a metalAnswer: Decreases with increases in tensile strength & decrease in grain size. Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting theAnswer: Washing action of metal. The refrigerant freon-12 is chemicallyAnswer: CCl₂F₂ Which of the following phenomenon will exhibit the minimum heat transfer?Answer: Conduction in air. Pyrometric cone equivalent (PCE) of a refractory is the measure of itsAnswer: Fusion point. Upto the critical radius of insulation, added insulation, willAnswer: Decrease heat loss and will have no effect beyond that. Highest melting (m.p = 3070°C) oxide refractory isAnswer: Thoria Limestone is added in the blast furnace (during pig iron manufacture) toAnswer: Form slag by combining with impurities. Cementite is in the lamellar form in the __________ phase of steel.Answer: Pearlitic Chrome magnesite brick is not used for lining theAnswer: Burning zone of limestone rotary kilns. To improve the machinability of steel, it is generally subjected toAnswer: Spherodising Which one contains minimum percentage of SiO₂?Answer: Sillimanite Silicon in steelAnswer: All 'a', 'b' & 'c'. Dislocations are __________ defects.Answer: Line Which of the following bricks should not be used, if the furnace is to be used intermit-tantly ?Answer: Silica bricks Refractory castables are used forAnswer: All (a), (b) and (c). The thickness of oxide film is y at time t. If K₁, K₂ and K₃ are the temperature dependent constants, the parabolic law of oxidation is given byAnswer: y² = 2k₁t + k₂ The largest consumer of refractories is the __________ industry.Answer: Metallurgical Which of the following has the least value of ultimate tensile strength (UTS) ?Answer: Medium carbon steel