⚗️ 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

Which of the following material is seldom used for pressure vessel construction ?Answer: Rimmed steel Flywheel is provided in a machine toAnswer: Smoothen the power impluses. The ratio of shear stress to shear strain is calledAnswer: Shear modulus Nickel is a __________ material.Answer: Ferromagnetic Grey cast iron (used for making underground water pipes and manhole covers) as compared to steel has higherAnswer: Machinability L.D. converters are generally lined withAnswer: Chrome magnesite When the weight of a ball inside the ball mill is just balanced by the centrifugal force,Answer: the ball abandons its circular path for a parabolic path. __________ is not a heat treatment process.Answer: Pakerising 25 per cent cut segmental baffle means that the baffleAnswer: Height is 75% of the I.D. of the shell. An ingot is hot forged to a 60% reduction in cross-section area. The percentage reduction in the volume for the above process isAnswer: 0 Liquid/petroleum fuel storage tanks are built underground (as in case of petrol pumps), when the storage capacity is less than __________ kilolitres.Answer: 45 Volute casing of a centrifugal pump does not facilitateAnswer: Conversion of the part of the pressure head to velocity head. Desert air coolers being rendered ineffective in rainy season is due toAnswer: High humidity The hydraulic radius of a circular pipe of diameter 'd' flowing full isAnswer: D/4 Lug support isAnswer: All (a), (b) and (c). Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column.Answer: Maintenance cost for valve and seive trays are comparatively more than bubble cap tray due to their relatively complicated construction features. With increase in the number of shell passes, the value of FTAnswer: Increases Holes of a sieve tray are arranged in triangular pitch of __________ times the hole diameter.Answer: 2.5 to 5 In case of a shell and tube heat exchanger, the minimum shell thickness for carbon steel (inclusive of corrosion allowance) depends on shell diameter and is in the range of __________ mm.Answer: 5-11 The stress developed in a material without any permanent set is called theAnswer: Elastic limit In a shell and tube heat exchanger, the 'tube pitch' is defined as theAnswer: Shortest centre to centre distance between adjacent tubes. Which of the following is not a valid assumption in continuous binary distillation for calculating the number of equilibrium stages by Mc-Cabe-Thiele's method ?Answer: Reflux is not a saturated liquid. The excess air required for the combustion of pulverised coal is of the order of about __________ percent.Answer: 15 Pick out the wrong statement.Answer: None of these Overall distillation column efficiency for most of the refinery columns can be given by (for μ = 0.07 - 1.4 cp and relative volatility < 4) (where η = overall column efficiency, % μ = molal average viscosity of feed at average column temperature and pressure, cp Δp = pressure drop per tray, psi)Answer: η = 17 - 61.1 log μ __________ of austenite decreases the hardenability in steel.Answer: Dissolved elements (except cobalt) A jig is used while __________ a hole.Answer: Drilling The value of fouling factor depends upon theAnswer: All (a), (b) and (c). In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about __________ cms.Answer: 10 At 100% relative humidity, the dew point temperature of moist air isAnswer: More than the wet bulb temperature.