Description : A moderator __________ the neutrons. (A) Slows down (B) Absorbs (C) Accelerates (D) Reflects
Last Answer : (A) Slows down
Description : Neutrons are slowed down in a nuclear reactor by – (1) Fissionable Material (2) Moderator (3) Control rods (4) Cooling system
Last Answer : (2) Moderator Explanation: In thermal nuclear reactors, the coolant acts as a moderator that must slow down the neutrons before they can be efficiently absorbed by the fuel. It allows neutrons to slow down to energies where they can easily cause a nucleus to fission.
Description : Neutrons are slowed down in a nuclear reactor by (1) Fissionable material (2) Moderator (3) Control rods (4) Cooling system
Last Answer : Moderator
Description : Which of the following terms refers to the energy released when an electron is added to a neutral atom? w) electrovalence x) electron affinity y) electroconductance z) none of these
Last Answer : ANSWER: X -- ELECTRON AFFINITY
Description : Which of the following terms refers to the number of molecules or ions attached to a central metallic atom? w) coordination number x) connection number y) bonding number z) none of these
Last Answer : ANSWER: W -- COORDINATION NUMBER
Description : Buffer solutions show which one of the following traits: w) absorb acid and base with only small changes in pH x) indefinite stability y) high elasticity z) abnormal density
Last Answer : ANSWER: W -- ABSORB ACID AND BASE WITH ONLY SMALL CHANGES IN pH
Description : Which of the following pairs of compounds could NOT be used to create a buffer solution? Would it be: w) HCL and NaCl (read: H - C - L and N - A - C - L) x) HCN and NaCN (read: H - C - N and N - A - C - N) y) NH3 ... - H - 4 - C - L) z) HNO2 and NaNO2 (read: H - N - O -2 and N - A - N - O - 2)
Last Answer : ANSWER: W -- HCL AND NaCl (read: H - C - L and N - A - C - L)
Description : The part of a nuclear power plant that prevents thermal pollution of lakes or rivers is the: w) reactor x) coolant/moderator y) cooling tower z) control rod
Last Answer : ANSWER: Y -- COOLING TOWER
Description : What substance was used as a moderator for the chain reaction in the first nuclear reactor? w) graphite x) boron y) water z) cadmium
Last Answer : ANSWER: W -- GRAPHITE
Description : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The neutrons from the source are of high speed and en
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission ... neutrons C. magnetic neutrons D. electric neutrons
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... water B. Graphite C. Beryllium D. Sodium
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... mass number only D. be all the above three
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission ... . absorbs thermal energy. Produced in the reactors
Description : The nuclei of heavy atoms generally contain: w) more electrons than neutrons x) more protons than electrons y) more neutrons than electrons z) more orbitals than electrons
Last Answer : ANSWER: Y -- MORE NEUTRONS THAN ELECTRONS
Description : Which of the following is the same for both radioactive iodine and stable iodine? w) number of neutrons x) mass number y) half-life z) chemical properties
Last Answer : ANSWER: Z -- CHEMICAL PROPERTIES
Description : The silver luster of the metals can be attributed to one of the following. It is attributed to their free w) protons x) ions y) neutrons z) electrons
Last Answer : ANSWER: Z -- ELECTRONS
Description : It is believed that carbon-14 in nature is slowly generated by the action of: w) protons on carbon-12 x) electrons on hydrogen y) cosmic rays on boron z) neutrons on nitrogen
Last Answer : ANSWER: Z -- NEUTRONS ON NITROGEN
Description : The Modulus of Elasticity for a material refers to: w) the ability of a material to resist corrosion x) the ratio of stress over strain y) the maximum load over the cross sectional area z) none of the above
Last Answer : ANSWER: X -- THE RATIO OF STRESS OVER STRAIN
Description : The dominant charge carriers in p-type semiconductors are: w) neutrons x) electrons y) protons z) holes
Last Answer : ANSWER: Z -- HOLES
Description : Photoelectric electricity is produced directly from solar energy when which of the following are absorbed in a semiconductor to create an electric current? w) protons x) electrons y) neutrons z) photons
Last Answer : ANSWER: Z -- PHOTONS
Description : The ability of an atom to absorb neutrons is its neutron capture cross section. The unit of measurement for neutron capture cross section is: w) the nucleus volume x) capture capacity y) resonance quotient z) barn
Last Answer : ANSWER: Z -- BARN
Description : In the fission of U235, what is the average number of neutrons produced in the fission reaction? w) 1.5 x) 2.5 y) 3.5 z) 4.5
Last Answer : ANSWER: X -- 2.5
Description : Most of the new atoms formed when atoms in a nuclear reactor capture neutrons without fissioning are: w) fission products x) activation products y) actinides z) lead isotopes
Last Answer : ANSWER: Y -- ACTINIDES
Description : A fast reactor uses: w) an extremely short time to get to the maximum operating reactivity. x) uranium-235 as fuel. y) heavy water as a coolant. z) essentially unmoderated neutrons.
Last Answer : ANSWER: Z -- ESSENTIALLY UNMODERATED NEUTRONS.
Description : Reactors in commercial nuclear power plants in the U.S. are often referred to as thermal reactors. A thermal reactor uses: w) fissionable plutonium-239 as fuel. x) a relatively low heat output. y) neutrons moderated to relatively low energies. z) liquid sodium as a coolant.
Last Answer : ANSWER: Y -- NEUTRONS MODERATED TO RELATIVELY LOW ENERGIES.
Description : Of the following, which non-fissioning element is used in the cooling water of nuclear power plants to help control the rate of the fission reaction by absorbing neutrons: w) zirconium x) boron y) krypton z) cesium
Last Answer : ANSWER: X -- BORON
Description : The binding energy of a nucleus is defined as one of the following. Is this definition: w) the energy equivalent to its mass x) the mass difference between its neutrons and protons y) the energy ... the difference between the mass of the nucleus and the sum of the masses of its protons and neutrons
Last Answer : ANSWER: Z -- THE DIFFERENCE BETWEEN THE MASS OF THE NUCLEUS AND THE UM
Description : In N-type semiconductors the majority of the carriers are: w) holes x) electrons y) protons z) neutrons
Last Answer : ANSWER: X -- ELECTRONS
Description : Which one of the following particles travels at the speed of light? w) neutrons x) electrons y) photons z) muons
Last Answer : ANSWER: Y -- PHOTONS
Description : Isotopes of an element have different numbers of: w) electrons x) protons y) neutrons z) leptons
Last Answer : ANSWER: Y -- NEUTRONS
Description : The neutrons in an atom: w) are part of the nuclear charge x) rotate about the nucleus in elliptical orbits y) vary in number with different isotopes z) are always equal in number to the total number of protons
Last Answer : ANSWER: Y -- VARY IN NUMBER WITH DIFFERENT ISOTOPES
Description : When an atomic nucleus emits a beta particle, one of its neutrons disintegrates into one of the following set of particles. Does it disintegrate into: w) a positron and an electron x) a proton, an ... and an antineutrino y) a proton, an electron, and a positron z) a neutrino and an antineutrino
Last Answer : ANSWER: X -- A PROTON, AN ELECTRON AND AN ANTINEUTRINO
Description : Endothermic refers to a process that w) does work x) gives off heat y) loses mass z) absorbs heat
Last Answer : ANSWER: Z -- ABSORBS HEAT
Description : Which of the following refers to an easily melted product of the reaction between the flux and the impurities of an ore? w) slag x) slurry y) slug z) none of the above
Last Answer : ANSWER: W -- SLAG
Description : Which of the following refers to the scattering of light by colloidal particles? w) Rutherford effect x) Tyndall effect (pron: tin-dahl) y) Thompson effect z) none of these
Last Answer : ANSWER: X -- TYNDALL EFFECT
Description : In a nuclear reactor the moderator is usually made of graphite placed between the fuel rods used to slow down neutrons all of the above none of the above?
Last Answer : Feel Free to Answer
Description : Ordinary water is not used as a moderator because, it (A) Has a low absorption cross-section (B) Has a low scattering cross-section (C) Absorbs neutrons (D) Does not absorb neutrons
Last Answer : (C) Absorbs neutrons
Description : A moderator is used in nuclear reactor in order to ? A. Accelerate the neutrons B. Slow down the speed of the neutrons (Answer) C. Increase the number of elections D. Decrease the number of electrons E. None of these
Last Answer : B. Slow down the speed of the neutrons (Answer)
Description : In terms of quality, what is the highest ranked coal? w) peat x) bituminous y) anthracite z) lignite
Last Answer : ANSWER: Y -- ANTHRACITE
Description : Which of the following terms denotes the polar molecules or negative ions clustered about a central positive ion? w) ligands x) isomers y) complex ions z) dipoles
Last Answer : ANSWER: W -- LIGAND
Description : Which of the following terms has as its definition: a mixture having continuous and dispersed phases? w) colloid x) solute y) suspension z) solvent
Last Answer : ANSWER: W -- COLLOID
Description : Which of the following terms means that a crystal has the ability to capture and hold water molecules? w) hydroponic x) hygroscopic y) hydrophobic z) hydropholectic
Last Answer : ANSWER: X -- HYGROSCOPIC
Description : Which of the following terms best fits the statement: "Process by which polysaccharides are degraded to monosaccharides." w) hydrolysis x) glycolosis y) lipogenesis z) none of the above
Last Answer : ANSWER: W -- HYDROLYSIS
Description : For which molecule can the bonding be described in terms of sp3 hybrid orbitals of the central atom? w) CH4 x) SF6 y) BF3 z) PCL5
Last Answer : ANSWER: B -- CH4
Description : The Rate Law expresses the rate of a reaction in terms of the concentrations of the: w) reactants x) products y) by-products z) catalysts
Last Answer : ANSWER: W -- REACTANTS
Description : The nickname, "Fool's Gold," refers to which of th following? w) calcite x) apatite y) fluorite z) pyrite
Last Answer : ANSWER: Z -- PYRITE
Description : The saltation of sand grains refers to the sand grains: w) being coated with salt x) moving in jumps and bounces y) moving in a steady stream z) being cemented together
Last Answer : ANSWER: X -- MOVING IN JUMPS AND BOUNCES
Description : Which of the following best illustrates feedback in development? (a) Tissue X secretes RNA which changes the development of tissue Y. (b) As tissue X develops, it secretes enzymes that inhibit the ... . (d) As tissue X develops, it secretes something that slows down the growth of tissue Y.
Last Answer : (c) As tissue X develops, it secretes something that induces tissue Y to develop
Description : If a material has the capacity to behave either as an acid or a base it is said to be: w) amorphous x) amphoteric y) anhydrous z) aklaline
Last Answer : ANSWER: X -- AMPHOTERIC
Description : This noncombustible liquid in its dry form is noncorrosive to common metals except aluminum. About 90% of all of this material which is manufactured goes into the production of chlorofluorocarbons. ... substance: w) carbon tetrachloride x) methylene chloride y) hydrogen chloride z) methyl fluoride
Last Answer : ANSWER: W -- CARBON TETRACHLORIDE