⚗️ 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

Fuel economy in furnaces can be achieved byAnswer: All (a), (b) and (c). Absorptivity of a grey body varies with theAnswer: Neither 'a' nor 'b'. Thermal efficiency of an open hearth furnace may be about __________ percent.Answer: 20 Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent.Answer: < 2 In radiative heat transfer, a grey surface is the one, which hasAnswer: Emissivity independent of wavelength. Which of the following is a rotary furnace?Answer: Lime kiln Overheating of satellites during re-entry to earth is controlled byAnswer: Cooling by flow of air over the surface. The most abundant metal present in the earth's crust is;Answer: Aluminium Which of the following variables affects the furnace capacity ?Answer: All (a), (b) and (c). In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on theAnswer: All (a), (b) and (c) In which of the following furnaces, the gases are sucked through the stock bed from below?Answer: Sintering machine Waste heat from the outgoing flue gases in a thermal power plant is recovered by a/anAnswer: All (a), (b) and (c) Recuperator isAnswer: A continuous waste heat recovery equipment. An improved and fuel efficient version of the pusher type reheating furnace is the __________ furnace.Answer: Walking beam Which of the following may be used to measure the rate of nuclear disintegration?Answer: Geiger-Muller Counter The decrease in the atomic number is not observed in case ofAnswer: β-emission The mass number of an element is not changed, when it emits __________ radiations.Answer: β & γ Which of the following is not a naturally occurring nuclear fuel ?Answer: Plutonium-239 An electron has a mass that is approximately __________ that of the proton.Answer: 1/1836 (approximately) Which is the most commonly used molten metal for cooling of nuclear reactors ?Answer: Sodium The amount of a radioactive material (having a half life of 100 years) remaining after 400 years will be __________ of its original weight.Answer: 1/16 The second underground nuclear test was conducted by India atAnswer: Pokhran Which of the following is artificially produced as it does not occur in nature ?Answer: Both (b) and (c) Gas cooling as compared to water cooling of nuclear reactorsAnswer: None of these The decay product of tritium (a beta emitter) isAnswer: Helium Heat is generated in a nuclear reactor (thermal) byAnswer: Fission of U-235 by neutrons. The time taken for a radioactive element to reduce to 50% of its original weight is __________ years, if its half life period is 12 years.Answer: 18 Which of the following may not need a moderator ?Answer: Fast breeder reactor The amount of a radioisotope remaining undecayed after a time equal to four times its half life, will be __________ percent.Answer: 6.25 Fast breeder reactors do notAnswer: Use Th-232 as fissile fuel.