581. The excess air required for the combustion of pulverised coal is of the order of about __________ percent.
A. 5
B. 15
C. 30
D. 45
✅ The correct answer is option B.
Basic Chemical Engineering MCQs
Practice Basic Chemical Engineering MCQs with answers and explanations to prepare for exams, interviews, and job tests. Our question bank covers fundamental topics such as units and dimensions, material and energy balances, fluid mechanics, thermodynamics, heat transfer, mass transfer, and chemical process basics. These multiple-choice questions are designed for students, fresh graduates, and competitive exam aspirants preparing for NTS, PPSC, FPSC, PEC exams, GATE, university entry tests, and recruitment assessments. Strengthen your core concepts and problem-solving skills with our updated Basic Chemical Engineering MCQs.
582. Commonly employed coolant for high pressure turbogenerator is
A. Air
B. Carbon dioxide
C. Hydrogen
D. Water
✅ The correct answer is option C.
583. In case of fluid moving machineries, the relationship between saturation temperature and pressure decides the process of
A. Water hammer
B. Cavitation
C. Flow separation
D. Turbulent mixing
✅ The correct answer is option B.
584. In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the
A. Range is 15°F
B. Approach is 10°F
C. Both A & B
D. Neither A nor B
✅ The correct answer is option C.
585. Electrical conductivities of semi-conductors are of the order of __________ ohm/cm.
A. 10-3
B. 103
C. 10-15
D. L015
✅ The correct answer is option A.
586. Pick out the wrong statement. Termination of polymerisation reaction occurs, if the
A. Catalyst supply is stopped
B. Monomer supply is exhausted
C. Impurities present in monomers interfere with the chemical reaction
D. Two ends of a chain of molecules join
✅ The correct answer is option A.
587. Oxygen content below __________ percent in air contaminated with nitrogen does not support combustion and is unsafe for humane exposure.
A. 18
B. 16
C. 14
D. 12
✅ The correct answer is option B.
588. With increasing carbon percent in steel beyond 0.8%, its ultimate tensile strength (UTS) and __________ is not affected.
A. Impact strength
B. Percent elongation
C. Hardness
D. Both B & C
✅ The correct answer is option A.
589. Out of the following, the materials having maximum magnetic permeability is
A. Silicon steel (Si = 4%)
B. Cast iron
C. Wrought iron
D. Mild steel
✅ The correct answer is option A.
590. Heating of an ore below its melting point in presence of excess of air is called
A. Calcination
B. Smelting
C. Roasting
D. Sublimation
✅ The correct answer is option C.