All Free Chemical Engineering MCQs with Answers

• 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.

• 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.

• 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.

• 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.

• 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…

• 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.

• 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.

• 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.

• 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.

• 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.

• 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.

• 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.

• 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…

• 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.

• 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.

• 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.

• 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…

• 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.

• A. Leaching with sulphuric acid
• B. Froth floatation technique
• C. Smelting in a furnace
• D. Dissolving in water

Explanation: Pitchblende is treated by leaching with sulphuric acid, which dissolves uranium compounds into solution for subsequent purification.

• A. Pitchblende
• B. Kyanite
• C. Carnotite
• D. Rescolite

Explanation: Kyanite is an aluminium silicate mineral, not a uranium ore. Pitchblende, carnotite and roscoelite, sometimes misspelled as “rescolite,”…