Free Chemical Process Principles MCQs with Answers

2,710 Chemical Process Principles MCQs from Chemical Engineering, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

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  • A. Deuterium
  • B. Tritium
  • C. Ortho-hydrogen
  • D. None of these

Explanation: Tritium is hydrogen-3 and contains one proton and two neutrons, making it radioactive.

Correct answer: Tritium
  • A. Fast breeder
  • B. Highly enriched uranium (85% U-235) fuelled
  • C. Homogeneous
  • D. Natural uranium fuelled heavy water cooled & moderated

Explanation: A CANDU reactor uses natural uranium fuel and heavy water as both moderator and coolant.

Correct answer: Natural uranium fuelled heavy water cooled & moderated
  • A. Candu reactor
  • B. Boiling water reactor (BWR)
  • C. Pressurised water reactor (PWR)
  • D. Molten sodium cooled reactor

Explanation: CANDU means Canada Deuterium Uranium and uses heavy water as its moderator.

Correct answer: Candu reactor
  • A. U-233
  • B. Th-232
  • C. Pu-239
  • D. U-235

Explanation: Thorium-232 is fertile because it can absorb a neutron and ultimately form fissile uranium-233.

Correct answer: Th-232
  • A. Only fissile material
  • B. Only fertile material
  • C. More than 0.71% of U-235
  • D. No impurities

Explanation: Natural uranium contains about 0.71% U-235, so uranium is called enriched when its U-235 concentration is increased above this value.

Correct answer: More than 0.71% of U-235
  • A. Lithium
  • B. Hydrogen
  • C. Deuterium
  • D. Helium

Explanation: Tritium is hydrogen-3 and undergoes beta-minus decay, converting a neutron into a proton and forming helium-3.

Correct answer: Helium
  • A. Logarithmic
  • B. Exponential
  • C. Linear
  • D. Inverse square

Explanation: Radioactive decay follows an exponential law, expressed as N = N₀e⁻ˡᵗ, where the number of undecayed nuclei decreases by a constant…

Correct answer: Exponential
  • A. Mildly alkaline (pH = 8) water
  • B. Mildly acidic (pH = 6) water
  • C. Ordinary water
  • D. None of these

Explanation: Light water is ordinary water, H₂O, in which hydrogen is mainly the common isotope protium.

Correct answer: Ordinary water
  • A. 2 x 10^23
  • B. 5 x 10^5
  • C. 6 x 10^32
  • D. 6 x 10^23

Explanation: One gram-atom means one mole of atoms, and one mole contains Avogadro's number, approximately 6.022 × 10²³ atoms.

Correct answer: 6 x 10^23
  • A. Deuterium and tritium
  • B. U-233
  • C. Thorium
  • D. Heavy water

Explanation: The most common fusion-reactor fuel mixture is deuterium and tritium, whose fusion produces helium and a large amount of energy.

Correct answer: Deuterium and tritium
  • A. Processing of uranium ore
  • B. Manufacture of nuclear fuel elements/assemblies
  • C. Treatment of spent fuel
  • D. None of these

Explanation: India's Nuclear Fuel Complex in Hyderabad manufactures nuclear fuel elements and fuel assemblies for reactors.

Correct answer: Manufacture of nuclear fuel elements/assemblies
  • A. Th-232
  • B. U-238
  • C. U-233
  • D. None of these

Explanation: U-233 is fissile, so it can sustain a chain reaction with slow neutrons; it is not classified as fertile.

Correct answer: U-233
  • A. Plutonium-239
  • B. Uranium-235
  • C. Uranium-233
  • D. Thorium-232

Explanation: Thorium-232 is non-fissile with thermal neutrons and is fertile because it can breed U-233 after neutron capture and decay.

Correct answer: Thorium-232
  • A. 5
  • B. 10
  • C. 20
  • D. 30

Explanation: Half-life is an intrinsic property of a radioactive isotope and does not depend on the amount present.

Correct answer: 10
  • A. Heating it
  • B. Surrounding it by neutron reflecting material
  • C. Cooling it
  • D. Surrounding it by neutron absorbing material

Explanation: A neutron reflector sends escaping neutrons back into the fissile core, increasing the chance of further fission and lowering the mass…

Correct answer: Surrounding it by neutron reflecting material
  • A. 9.31
  • B. 93.1
  • C. 931
  • D. 9310

Explanation: Using E = mc², the mass defect corresponding to 1 amu is approximately 931 MeV.

Correct answer: 931
  • A. Graphite as moderator
  • B. Water as coolant
  • C. Molten sodium as coolant as well as moderator
  • D. U-235 as fuel

Explanation: Fast breeder reactors use fast neutrons and therefore do not require a moderator; liquid sodium is commonly used as the coolant.

Correct answer: U-235 as fuel
  • A. Thorium
  • B. Polonium
  • C. Hafnium
  • D. Uranium

Explanation: Monazite sand is a major source of thorium because it contains thorium phosphate along with rare-earth minerals.

Correct answer: Thorium
  • A. None of these
  • B. bombardment on different materials
  • C. Accelerating the neutrons
  • D. Power generation
  • E. Producing high neutron flux 1012-1013 neutrons/cm2, sec and studying the effect of neutron

Explanation: Research reactors are designed to provide intense neutron fluxes for neutron-beam experiments, isotope production, and studying neutron…

Correct answer: Producing high neutron flux 1012-1013 neutrons/cm2, sec and studying the effect of neutron
  • A. Number of electrons
  • B. Atomic numbers
  • C. Number of protons
  • D. Atomic weights

Explanation: Isotopes have the same atomic number, proton count, and, for neutral atoms, electron count.

Correct answer: Atomic weights